diff --git a/api/test-current.txt b/api/test-current.txt
index 0902fc6..7256e5c 100644
--- a/api/test-current.txt
+++ b/api/test-current.txt
@@ -6226,11 +6226,28 @@
   }
 
   public class WindowConfiguration implements java.lang.Comparable android.os.Parcelable {
+    ctor public WindowConfiguration();
     method public int compareTo(android.app.WindowConfiguration);
     method public int describeContents();
+    method public int getActivityType();
+    method public android.graphics.Rect getAppBounds();
+    method public int getWindowingMode();
+    method public void setActivityType(int);
+    method public void setAppBounds(android.graphics.Rect);
+    method public void setTo(android.app.WindowConfiguration);
+    method public void setWindowingMode(int);
     method public void writeToParcel(android.os.Parcel, int);
+    field public static final int ACTIVITY_TYPE_ASSISTANT = 4; // 0x4
     field public static final int ACTIVITY_TYPE_HOME = 2; // 0x2
     field public static final int ACTIVITY_TYPE_RECENTS = 3; // 0x3
+    field public static final int ACTIVITY_TYPE_STANDARD = 1; // 0x1
+    field public static final int ACTIVITY_TYPE_UNDEFINED = 0; // 0x0
+    field public static final int WINDOWING_MODE_FREEFORM = 5; // 0x5
+    field public static final int WINDOWING_MODE_FULLSCREEN = 1; // 0x1
+    field public static final int WINDOWING_MODE_PINNED = 2; // 0x2
+    field public static final int WINDOWING_MODE_SPLIT_SCREEN_PRIMARY = 3; // 0x3
+    field public static final int WINDOWING_MODE_SPLIT_SCREEN_SECONDARY = 4; // 0x4
+    field public static final int WINDOWING_MODE_UNDEFINED = 0; // 0x0
   }
 
 }
@@ -11328,6 +11345,7 @@
     field public int smallestScreenWidthDp;
     field public int touchscreen;
     field public int uiMode;
+    field public final android.app.WindowConfiguration windowConfiguration;
   }
 
   public class ObbInfo implements android.os.Parcelable {
diff --git a/core/java/android/app/WindowConfiguration.java b/core/java/android/app/WindowConfiguration.java
index 5d87e1c..07eb5de 100644
--- a/core/java/android/app/WindowConfiguration.java
+++ b/core/java/android/app/WindowConfiguration.java
@@ -17,6 +17,9 @@
 package android.app;
 
 import static android.app.ActivityThread.isSystem;
+import static android.app.WindowConfigurationProto.ACTIVITY_TYPE;
+import static android.app.WindowConfigurationProto.APP_BOUNDS;
+import static android.app.WindowConfigurationProto.WINDOWING_MODE;
 
 import android.annotation.IntDef;
 import android.annotation.NonNull;
@@ -25,6 +28,7 @@
 import android.graphics.Rect;
 import android.os.Parcel;
 import android.os.Parcelable;
+import android.util.proto.ProtoOutputStream;
 import android.view.DisplayInfo;
 
 /**
@@ -48,26 +52,20 @@
     /** The current windowing mode of the configuration. */
     private @WindowingMode int mWindowingMode;
 
-    /** Windowing mode is currently not defined.
-     * @hide */
+    /** Windowing mode is currently not defined. */
     public static final int WINDOWING_MODE_UNDEFINED = 0;
-    /** Occupies the full area of the screen or the parent container.
-     * @hide */
+    /** Occupies the full area of the screen or the parent container. */
     public static final int WINDOWING_MODE_FULLSCREEN = 1;
-    /** Always on-top (always visible). of other siblings in its parent container.
-     * @hide */
+    /** Always on-top (always visible). of other siblings in its parent container. */
     public static final int WINDOWING_MODE_PINNED = 2;
-    /** The primary container driving the screen to be in split-screen mode.
-     * @hide */
+    /** The primary container driving the screen to be in split-screen mode. */
     public static final int WINDOWING_MODE_SPLIT_SCREEN_PRIMARY = 3;
     /**
      * The containers adjacent to the {@link #WINDOWING_MODE_SPLIT_SCREEN_PRIMARY} container in
      * split-screen mode.
-     * @hide
      */
     public static final int WINDOWING_MODE_SPLIT_SCREEN_SECONDARY = 4;
-    /** Can be freely resized within its parent container.
-     * @hide */
+    /** Can be freely resized within its parent container. */
     public static final int WINDOWING_MODE_FREEFORM = 5;
 
     /** @hide */
@@ -84,18 +82,15 @@
     /** The current activity type of the configuration. */
     private @ActivityType int mActivityType;
 
-    /** Activity type is currently not defined.
-     * @hide */
+    /** Activity type is currently not defined. */
     public static final int ACTIVITY_TYPE_UNDEFINED = 0;
-    /** Standard activity type. Nothing special about the activity...
-     * @hide */
+    /** Standard activity type. Nothing special about the activity... */
     public static final int ACTIVITY_TYPE_STANDARD = 1;
     /** Home/Launcher activity type. */
     public static final int ACTIVITY_TYPE_HOME = 2;
     /** Recents/Overview activity type. */
     public static final int ACTIVITY_TYPE_RECENTS = 3;
-    /** Assistant activity type.
-     * @hide */
+    /** Assistant activity type. */
     public static final int ACTIVITY_TYPE_ASSISTANT = 4;
 
     /** @hide */
@@ -127,7 +122,6 @@
             })
     public @interface WindowConfig {}
 
-    /** @hide */
     public WindowConfiguration() {
         unset();
     }
@@ -176,7 +170,6 @@
      * Set {@link #mAppBounds} to the input Rect.
      * @param rect The rect value to set {@link #mAppBounds} to.
      * @see #getAppBounds()
-     * @hide
      */
     public void setAppBounds(Rect rect) {
         if (rect == null) {
@@ -200,26 +193,20 @@
         mAppBounds.set(left, top, right, bottom);
     }
 
-    /**
-     * @see #setAppBounds(Rect)
-     * @hide
-     */
+    /** @see #setAppBounds(Rect) */
     public Rect getAppBounds() {
         return mAppBounds;
     }
 
-    /** @hide */
     public void setWindowingMode(@WindowingMode int windowingMode) {
         mWindowingMode = windowingMode;
     }
 
-    /** @hide */
     @WindowingMode
     public int getWindowingMode() {
         return mWindowingMode;
     }
 
-    /** @hide */
     public void setActivityType(@ActivityType int activityType) {
         if (mActivityType == activityType) {
             return;
@@ -237,13 +224,11 @@
         mActivityType = activityType;
     }
 
-    /** @hide */
     @ActivityType
     public int getActivityType() {
         return mActivityType;
     }
 
-    /** @hide */
     public void setTo(WindowConfiguration other) {
         setAppBounds(other.mAppBounds);
         setWindowingMode(other.mWindowingMode);
@@ -382,6 +367,24 @@
     }
 
     /**
+     * Write to a protocol buffer output stream.
+     * Protocol buffer message definition at {@link android.app.WindowConfigurationProto}
+     *
+     * @param protoOutputStream Stream to write the WindowConfiguration object to.
+     * @param fieldId           Field Id of the WindowConfiguration as defined in the parent message
+     * @hide
+     */
+    public void writeToProto(ProtoOutputStream protoOutputStream, long fieldId) {
+        final long token = protoOutputStream.start(fieldId);
+        if (mAppBounds != null) {
+            mAppBounds.writeToProto(protoOutputStream, APP_BOUNDS);
+        }
+        protoOutputStream.write(WINDOWING_MODE, mWindowingMode);
+        protoOutputStream.write(ACTIVITY_TYPE, mActivityType);
+        protoOutputStream.end(token);
+    }
+
+    /**
      * Returns true if the activities associated with this window configuration display a shadow
      * around their border.
      * @hide
diff --git a/core/java/android/content/res/Configuration.java b/core/java/android/content/res/Configuration.java
index 780e6f7..1310e30 100644
--- a/core/java/android/content/res/Configuration.java
+++ b/core/java/android/content/res/Configuration.java
@@ -16,9 +16,20 @@
 
 package android.content.res;
 
+import static android.content.ConfigurationProto.DENSITY_DPI;
+import static android.content.ConfigurationProto.FONT_SCALE;
+import static android.content.ConfigurationProto.ORIENTATION;
+import static android.content.ConfigurationProto.SCREEN_HEIGHT_DP;
+import static android.content.ConfigurationProto.SCREEN_LAYOUT;
+import static android.content.ConfigurationProto.SCREEN_WIDTH_DP;
+import static android.content.ConfigurationProto.SMALLEST_SCREEN_WIDTH_DP;
+import static android.content.ConfigurationProto.UI_MODE;
+import static android.content.ConfigurationProto.WINDOW_CONFIGURATION;
+
 import android.annotation.IntDef;
 import android.annotation.NonNull;
 import android.annotation.Nullable;
+import android.annotation.TestApi;
 import android.app.WindowConfiguration;
 import android.content.pm.ActivityInfo;
 import android.content.pm.ActivityInfo.Config;
@@ -27,6 +38,7 @@
 import android.os.Parcel;
 import android.os.Parcelable;
 import android.text.TextUtils;
+import android.util.proto.ProtoOutputStream;
 import android.view.View;
 
 import com.android.internal.util.XmlUtils;
@@ -295,11 +307,12 @@
     public int screenLayout;
 
     /**
-     * @hide
      * Configuration relating to the windowing state of the object associated with this
      * Configuration. Contents of this field are not intended to affect resources, but need to be
      * communicated and propagated at the same time as the rest of Configuration.
+     * @hide
      */
+    @TestApi
     public final WindowConfiguration windowConfiguration = new WindowConfiguration();
 
     /** @hide */
@@ -1054,6 +1067,28 @@
     }
 
     /**
+     * Write to a protocol buffer output stream.
+     * Protocol buffer message definition at {@link android.content.ConfigurationProto}
+     *
+     * @param protoOutputStream Stream to write the Configuration object to.
+     * @param fieldId           Field Id of the Configuration as defined in the parent message
+     * @hide
+     */
+    public void writeToProto(ProtoOutputStream protoOutputStream, long fieldId) {
+        final long token = protoOutputStream.start(fieldId);
+        protoOutputStream.write(FONT_SCALE, fontScale);
+        protoOutputStream.write(SCREEN_LAYOUT, screenLayout);
+        protoOutputStream.write(ORIENTATION, orientation);
+        protoOutputStream.write(UI_MODE, uiMode);
+        protoOutputStream.write(SCREEN_WIDTH_DP, screenWidthDp);
+        protoOutputStream.write(SCREEN_HEIGHT_DP, screenHeightDp);
+        protoOutputStream.write(SMALLEST_SCREEN_WIDTH_DP, smallestScreenWidthDp);
+        protoOutputStream.write(DENSITY_DPI, densityDpi);
+        windowConfiguration.writeToProto(protoOutputStream, WINDOW_CONFIGURATION);
+        protoOutputStream.end(token);
+    }
+
+    /**
      * Set this object to the system defaults.
      */
     public void setToDefaults() {
diff --git a/core/proto/android/app/window_configuration.proto b/core/proto/android/app/window_configuration.proto
new file mode 100644
index 0000000..03910df
--- /dev/null
+++ b/core/proto/android/app/window_configuration.proto
@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+syntax = "proto3";
+
+option java_package = "android.app";
+option java_multiple_files = true;
+
+package android.app;
+
+import "frameworks/base/core/proto/android/graphics/rect.proto";
+
+/** Proto representation for WindowConfiguration.java class. */
+message WindowConfigurationProto {
+  .android.graphics.RectProto app_bounds = 1;
+  int32 windowing_mode = 2;
+  int32 activity_type = 3;
+}
diff --git a/core/proto/android/content/configuration.proto b/core/proto/android/content/configuration.proto
index f46b73a..804e0b4 100644
--- a/core/proto/android/content/configuration.proto
+++ b/core/proto/android/content/configuration.proto
@@ -21,6 +21,7 @@
 
 package android.content;
 
+import "frameworks/base/core/proto/android/app/window_configuration.proto";
 import "frameworks/base/core/proto/android/content/locale.proto";
 
 /**
@@ -43,5 +44,6 @@
   uint32 screen_height_dp = 14;
   uint32 smallest_screen_width_dp = 15;
   uint32 density_dpi = 16;
+  .android.app.WindowConfigurationProto window_configuration = 17;
 }
 
diff --git a/core/proto/android/server/windowmanagerservice.proto b/core/proto/android/server/windowmanagerservice.proto
index ee8a6dc..d177f1c 100644
--- a/core/proto/android/server/windowmanagerservice.proto
+++ b/core/proto/android/server/windowmanagerservice.proto
@@ -16,6 +16,7 @@
 
 syntax = "proto3";
 
+import "frameworks/base/core/proto/android/content/configuration.proto";
 import "frameworks/base/core/proto/android/graphics/rect.proto";
 import "frameworks/base/core/proto/android/view/displayinfo.proto";
 import "frameworks/base/core/proto/android/view/windowlayoutparams.proto";
@@ -26,17 +27,23 @@
 
 message WindowManagerServiceProto {
   WindowManagerPolicyProto policy = 1;
-  /* window manager hierarchy structure */
+  /* window hierarchy root */
+  RootWindowContainerProto root_window_container = 2;
+  IdentifierProto focused_window = 3;
+  string focused_app = 4;
+  IdentifierProto input_method_window = 5;
+  bool display_frozen = 6;
+  int32 rotation = 7;
+  int32 last_orientation = 8;
+  AppTransitionProto app_transition = 9;
+}
+
+/* represents DisplayContent */
+message RootWindowContainerProto {
+  WindowContainerProto window_container = 1;
   repeated DisplayProto displays = 2;
   /* window references in top down z order */
   repeated IdentifierProto windows = 3;
-  IdentifierProto focused_window = 4;
-  string focused_app = 5;
-  IdentifierProto input_method_window = 6;
-  bool display_frozen = 7;
-  int32 rotation = 8;
-  int32 last_orientation = 9;
-  AppTransitionProto app_transition = 10;
 }
 
 /* represents PhoneWindowManager */
@@ -81,18 +88,19 @@
 
 /* represents DisplayContent */
 message DisplayProto {
-  int32 id = 1;
-  repeated StackProto stacks = 2;
-  DockedStackDividerControllerProto docked_stack_divider_controller = 3;
-  PinnedStackControllerProto pinned_stack_controller = 4;
+  WindowContainerProto window_container = 1;
+  int32 id = 2;
+  repeated StackProto stacks = 3;
+  DockedStackDividerControllerProto docked_stack_divider_controller = 4;
+  PinnedStackControllerProto pinned_stack_controller = 5;
   /* non app windows */
-  repeated WindowTokenProto above_app_windows = 5;
-  repeated WindowTokenProto below_app_windows = 6;
-  repeated WindowTokenProto ime_windows = 7;
-  int32 dpi = 8;
-  .android.view.DisplayInfoProto display_info = 9;
-  int32 rotation = 10;
-  ScreenRotationAnimationProto screen_rotation_animation = 11;
+  repeated WindowTokenProto above_app_windows = 6;
+  repeated WindowTokenProto below_app_windows = 7;
+  repeated WindowTokenProto ime_windows = 8;
+  int32 dpi = 9;
+  .android.view.DisplayInfoProto display_info = 10;
+  int32 rotation = 11;
+  ScreenRotationAnimationProto screen_rotation_animation = 12;
 }
 
 
@@ -109,20 +117,22 @@
 
 /* represents TaskStack */
 message StackProto {
-  int32 id = 1;
-  repeated TaskProto tasks = 2;
-  bool fills_parent = 3;
-  .android.graphics.RectProto bounds = 4;
-  bool animation_background_surface_is_dimming = 5;
+  WindowContainerProto window_container = 1;
+  int32 id = 2;
+  repeated TaskProto tasks = 3;
+  bool fills_parent = 4;
+  .android.graphics.RectProto bounds = 5;
+  bool animation_background_surface_is_dimming = 6;
 }
 
 /* represents Task */
 message TaskProto {
-  int32 id = 1;
-  repeated AppWindowTokenProto app_window_tokens = 2;
-  bool fills_parent = 3;
-  .android.graphics.RectProto bounds = 4;
-  .android.graphics.RectProto temp_inset_bounds = 5;
+  WindowContainerProto window_container = 1;
+  int32 id = 2;
+  repeated AppWindowTokenProto app_window_tokens = 3;
+  bool fills_parent = 4;
+  .android.graphics.RectProto bounds = 5;
+  .android.graphics.RectProto temp_inset_bounds = 6;
 }
 
 /* represents AppWindowToken */
@@ -134,26 +144,28 @@
 
 /* represents WindowToken */
 message WindowTokenProto {
-  int32 hash_code = 1;
-  repeated WindowStateProto windows = 2;
+  WindowContainerProto window_container = 1;
+  int32 hash_code = 2;
+  repeated WindowStateProto windows = 3;
 }
 
 /* represents WindowState */
 message WindowStateProto {
-  IdentifierProto identifier = 1;
-  int32 display_id = 2;
-  int32 stack_id = 3;
-  .android.view.WindowLayoutParamsProto attributes = 4;
-  .android.graphics.RectProto given_content_insets = 5;
-  .android.graphics.RectProto frame = 6;
-  .android.graphics.RectProto containing_frame = 7;
-  .android.graphics.RectProto parent_frame = 8;
-  .android.graphics.RectProto content_frame = 9;
-  .android.graphics.RectProto content_insets = 10;
-  .android.graphics.RectProto surface_insets = 11;
-  WindowStateAnimatorProto animator = 12;
-  bool animating_exit = 13;
-  repeated WindowStateProto child_windows = 14;
+  WindowContainerProto window_container = 1;
+  IdentifierProto identifier = 2;
+  int32 display_id = 3;
+  int32 stack_id = 4;
+  .android.view.WindowLayoutParamsProto attributes = 5;
+  .android.graphics.RectProto given_content_insets = 6;
+  .android.graphics.RectProto frame = 7;
+  .android.graphics.RectProto containing_frame = 8;
+  .android.graphics.RectProto parent_frame = 9;
+  .android.graphics.RectProto content_frame = 10;
+  .android.graphics.RectProto content_insets = 11;
+  .android.graphics.RectProto surface_insets = 12;
+  WindowStateAnimatorProto animator = 13;
+  bool animating_exit = 14;
+  repeated WindowStateProto child_windows = 15;
 }
 
 message IdentifierProto {
@@ -178,4 +190,17 @@
 message ScreenRotationAnimationProto {
   bool started = 1;
   bool animation_running = 2;
-}
\ No newline at end of file
+}
+
+/* represents WindowContainer */
+message WindowContainerProto {
+  ConfigurationContainerProto configuration_container = 1;
+  int32 orientation = 2;
+}
+
+/* represents ConfigurationContainer */
+message ConfigurationContainerProto {
+  .android.content.ConfigurationProto override_configuration = 1;
+  .android.content.ConfigurationProto full_configuration = 2;
+  .android.content.ConfigurationProto merged_override_configuration = 3;
+}
diff --git a/services/core/java/com/android/server/wm/AppWindowToken.java b/services/core/java/com/android/server/wm/AppWindowToken.java
index ea2f305..2d1fc91 100644
--- a/services/core/java/com/android/server/wm/AppWindowToken.java
+++ b/services/core/java/com/android/server/wm/AppWindowToken.java
@@ -53,6 +53,7 @@
 import static com.android.server.wm.proto.AppWindowTokenProto.NAME;
 import static com.android.server.wm.proto.AppWindowTokenProto.WINDOW_TOKEN;
 
+import android.annotation.CallSuper;
 import android.annotation.NonNull;
 import android.app.Activity;
 import android.content.res.Configuration;
@@ -1620,8 +1621,9 @@
         }
     }
 
+    @CallSuper
     @Override
-    void writeToProto(ProtoOutputStream proto, long fieldId) {
+    public void writeToProto(ProtoOutputStream proto, long fieldId) {
         final long token = proto.start(fieldId);
         writeNameToProto(proto, NAME);
         super.writeToProto(proto, WINDOW_TOKEN);
diff --git a/services/core/java/com/android/server/wm/ConfigurationContainer.java b/services/core/java/com/android/server/wm/ConfigurationContainer.java
index 28ba9b3..1da94da 100644
--- a/services/core/java/com/android/server/wm/ConfigurationContainer.java
+++ b/services/core/java/com/android/server/wm/ConfigurationContainer.java
@@ -24,9 +24,14 @@
 import static android.app.WindowConfiguration.WINDOWING_MODE_SPLIT_SCREEN_PRIMARY;
 import static android.app.WindowConfiguration.WINDOWING_MODE_SPLIT_SCREEN_SECONDARY;
 import static android.app.WindowConfiguration.activityTypeToString;
+import static com.android.server.wm.proto.ConfigurationContainerProto.FULL_CONFIGURATION;
+import static com.android.server.wm.proto.ConfigurationContainerProto.MERGED_OVERRIDE_CONFIGURATION;
+import static com.android.server.wm.proto.ConfigurationContainerProto.OVERRIDE_CONFIGURATION;
 
+import android.annotation.CallSuper;
 import android.app.WindowConfiguration;
 import android.content.res.Configuration;
+import android.util.proto.ProtoOutputStream;
 
 import java.util.ArrayList;
 
@@ -252,6 +257,24 @@
         }
     }
 
+    /**
+     * Write to a protocol buffer output stream. Protocol buffer message definition is at
+     * {@link com.android.server.wm.proto.ConfigurationContainerProto}.
+     *
+     * @param protoOutputStream Stream to write the ConfigurationContainer object to.
+     * @param fieldId           Field Id of the ConfigurationContainer as defined in the parent
+     *                          message.
+     * @hide
+     */
+    @CallSuper
+    public void writeToProto(ProtoOutputStream protoOutputStream, long fieldId) {
+        final long token = protoOutputStream.start(fieldId);
+        mOverrideConfiguration.writeToProto(protoOutputStream, OVERRIDE_CONFIGURATION);
+        mFullConfiguration.writeToProto(protoOutputStream, FULL_CONFIGURATION);
+        mMergedOverrideConfiguration.writeToProto(protoOutputStream, MERGED_OVERRIDE_CONFIGURATION);
+        protoOutputStream.end(token);
+    }
+
     abstract protected int getChildCount();
 
     abstract protected E getChildAt(int index);
diff --git a/services/core/java/com/android/server/wm/DisplayContent.java b/services/core/java/com/android/server/wm/DisplayContent.java
index 6cf608a..817a01c 100644
--- a/services/core/java/com/android/server/wm/DisplayContent.java
+++ b/services/core/java/com/android/server/wm/DisplayContent.java
@@ -112,7 +112,9 @@
 import static com.android.server.wm.proto.DisplayProto.ROTATION;
 import static com.android.server.wm.proto.DisplayProto.SCREEN_ROTATION_ANIMATION;
 import static com.android.server.wm.proto.DisplayProto.STACKS;
+import static com.android.server.wm.proto.DisplayProto.WINDOW_CONTAINER;
 
+import android.annotation.CallSuper;
 import android.annotation.NonNull;
 import android.app.ActivityManager.StackId;
 import android.app.WindowConfiguration;
@@ -2119,8 +2121,11 @@
         }
     }
 
-    void writeToProto(ProtoOutputStream proto, long fieldId) {
+    @CallSuper
+    @Override
+    public void writeToProto(ProtoOutputStream proto, long fieldId) {
         final long token = proto.start(fieldId);
+        super.writeToProto(proto, WINDOW_CONTAINER);
         proto.write(ID, mDisplayId);
         for (int stackNdx = mTaskStackContainers.size() - 1; stackNdx >= 0; --stackNdx) {
             final TaskStack stack = mTaskStackContainers.get(stackNdx);
diff --git a/services/core/java/com/android/server/wm/RootWindowContainer.java b/services/core/java/com/android/server/wm/RootWindowContainer.java
index 8a74976..227e4b2 100644
--- a/services/core/java/com/android/server/wm/RootWindowContainer.java
+++ b/services/core/java/com/android/server/wm/RootWindowContainer.java
@@ -16,6 +16,7 @@
 
 package com.android.server.wm;
 
+import android.annotation.CallSuper;
 import android.content.res.Configuration;
 import android.graphics.Rect;
 import android.hardware.power.V1_0.PowerHint;
@@ -89,8 +90,9 @@
 import static com.android.server.wm.WindowSurfacePlacer.SET_UPDATE_ROTATION;
 import static com.android.server.wm.WindowSurfacePlacer.SET_WALLPAPER_ACTION_PENDING;
 import static com.android.server.wm.WindowSurfacePlacer.SET_WALLPAPER_MAY_CHANGE;
-import static com.android.server.wm.proto.WindowManagerServiceProto.DISPLAYS;
-import static com.android.server.wm.proto.WindowManagerServiceProto.WINDOWS;
+import static com.android.server.wm.proto.RootWindowContainerProto.DISPLAYS;
+import static com.android.server.wm.proto.RootWindowContainerProto.WINDOWS;
+import static com.android.server.wm.proto.RootWindowContainerProto.WINDOW_CONTAINER;
 
 /** Root {@link WindowContainer} for the device. */
 class RootWindowContainer extends WindowContainer<DisplayContent> {
@@ -1077,7 +1079,11 @@
         }
     }
 
-    void writeToProto(ProtoOutputStream proto) {
+    @CallSuper
+    @Override
+    public void writeToProto(ProtoOutputStream proto, long fieldId) {
+        final long token = proto.start(fieldId);
+        super.writeToProto(proto, WINDOW_CONTAINER);
         if (mService.mDisplayReady) {
             final int count = mChildren.size();
             for (int i = 0; i < count; ++i) {
@@ -1088,6 +1094,7 @@
         forAllWindows((w) -> {
             w.writeIdentifierToProto(proto, WINDOWS);
         }, true);
+        proto.end(token);
     }
 
     @Override
diff --git a/services/core/java/com/android/server/wm/Task.java b/services/core/java/com/android/server/wm/Task.java
index 55b6c91..7464a9b 100644
--- a/services/core/java/com/android/server/wm/Task.java
+++ b/services/core/java/com/android/server/wm/Task.java
@@ -34,7 +34,9 @@
 import static com.android.server.wm.proto.TaskProto.FILLS_PARENT;
 import static com.android.server.wm.proto.TaskProto.ID;
 import static com.android.server.wm.proto.TaskProto.TEMP_INSET_BOUNDS;
+import static com.android.server.wm.proto.TaskProto.WINDOW_CONTAINER;
 
+import android.annotation.CallSuper;
 import android.app.ActivityManager.StackId;
 import android.app.ActivityManager.TaskDescription;
 import android.content.pm.ActivityInfo;
@@ -735,8 +737,11 @@
         return "Task=" + mTaskId;
     }
 
-    void writeToProto(ProtoOutputStream proto, long fieldId) {
+    @CallSuper
+    @Override
+    public void writeToProto(ProtoOutputStream proto, long fieldId) {
         final long token = proto.start(fieldId);
+        super.writeToProto(proto, WINDOW_CONTAINER);
         proto.write(ID, mTaskId);
         for (int i = mChildren.size() - 1; i >= 0; i--) {
             final AppWindowToken appWindowToken = mChildren.get(i);
diff --git a/services/core/java/com/android/server/wm/TaskStack.java b/services/core/java/com/android/server/wm/TaskStack.java
index 4664dcb..126d820 100644
--- a/services/core/java/com/android/server/wm/TaskStack.java
+++ b/services/core/java/com/android/server/wm/TaskStack.java
@@ -41,7 +41,9 @@
 import static com.android.server.wm.proto.StackProto.FILLS_PARENT;
 import static com.android.server.wm.proto.StackProto.ID;
 import static com.android.server.wm.proto.StackProto.TASKS;
+import static com.android.server.wm.proto.StackProto.WINDOW_CONTAINER;
 
+import android.annotation.CallSuper;
 import android.app.ActivityManager.StackId;
 import android.content.res.Configuration;
 import android.graphics.Rect;
@@ -1219,8 +1221,11 @@
         return mMinimizeAmount != 0f;
     }
 
-    void writeToProto(ProtoOutputStream proto, long fieldId) {
+    @CallSuper
+    @Override
+    public void writeToProto(ProtoOutputStream proto, long fieldId) {
         final long token = proto.start(fieldId);
+        super.writeToProto(proto, WINDOW_CONTAINER);
         proto.write(ID, mStackId);
         for (int taskNdx = mChildren.size() - 1; taskNdx >= 0; taskNdx--) {
             mChildren.get(taskNdx).writeToProto(proto, TASKS);
diff --git a/services/core/java/com/android/server/wm/WindowContainer.java b/services/core/java/com/android/server/wm/WindowContainer.java
index 926719d..40923c8 100644
--- a/services/core/java/com/android/server/wm/WindowContainer.java
+++ b/services/core/java/com/android/server/wm/WindowContainer.java
@@ -19,12 +19,14 @@
 import static android.content.pm.ActivityInfo.SCREEN_ORIENTATION_BEHIND;
 import static android.content.pm.ActivityInfo.SCREEN_ORIENTATION_UNSET;
 import static android.content.pm.ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED;
-import static android.content.res.Configuration.EMPTY;
+import static com.android.server.wm.proto.WindowContainerProto.CONFIGURATION_CONTAINER;
+import static com.android.server.wm.proto.WindowContainerProto.ORIENTATION;
 
 import android.annotation.CallSuper;
 import android.content.res.Configuration;
 import android.util.Pools;
 
+import android.util.proto.ProtoOutputStream;
 import com.android.internal.util.ToBooleanFunction;
 
 import java.util.Comparator;
@@ -685,6 +687,23 @@
         }
     }
 
+    /**
+     * Write to a protocol buffer output stream. Protocol buffer message definition is at
+     * {@link com.android.server.wm.proto.WindowContainerProto}.
+     *
+     * @param protoOutputStream Stream to write the WindowContainer object to.
+     * @param fieldId           Field Id of the WindowContainer as defined in the parent message.
+     * @hide
+     */
+    @CallSuper
+    @Override
+    public void writeToProto(ProtoOutputStream protoOutputStream, long fieldId) {
+        final long token = protoOutputStream.start(fieldId);
+        super.writeToProto(protoOutputStream, CONFIGURATION_CONTAINER);
+        protoOutputStream.write(ORIENTATION, mOrientation);
+        protoOutputStream.end(token);
+    }
+
     String getName() {
         return toString();
     }
diff --git a/services/core/java/com/android/server/wm/WindowManagerService.java b/services/core/java/com/android/server/wm/WindowManagerService.java
index 32ee51c..6f79648 100644
--- a/services/core/java/com/android/server/wm/WindowManagerService.java
+++ b/services/core/java/com/android/server/wm/WindowManagerService.java
@@ -109,6 +109,7 @@
 import static com.android.server.wm.proto.WindowManagerServiceProto.INPUT_METHOD_WINDOW;
 import static com.android.server.wm.proto.WindowManagerServiceProto.LAST_ORIENTATION;
 import static com.android.server.wm.proto.WindowManagerServiceProto.POLICY;
+import static com.android.server.wm.proto.WindowManagerServiceProto.ROOT_WINDOW_CONTAINER;
 import static com.android.server.wm.proto.WindowManagerServiceProto.ROTATION;
 
 import android.Manifest;
@@ -6505,7 +6506,7 @@
 
     private void writeToProtoLocked(ProtoOutputStream proto) {
         mPolicy.writeToProto(proto, POLICY);
-        mRoot.writeToProto(proto);
+        mRoot.writeToProto(proto, ROOT_WINDOW_CONTAINER);
         if (mCurrentFocus != null) {
             mCurrentFocus.writeIdentifierToProto(proto, FOCUSED_WINDOW);
         }
diff --git a/services/core/java/com/android/server/wm/WindowState.java b/services/core/java/com/android/server/wm/WindowState.java
index 1b05566..8a2cb5a 100644
--- a/services/core/java/com/android/server/wm/WindowState.java
+++ b/services/core/java/com/android/server/wm/WindowState.java
@@ -116,7 +116,9 @@
 import static com.android.server.wm.proto.WindowStateProto.PARENT_FRAME;
 import static com.android.server.wm.proto.WindowStateProto.STACK_ID;
 import static com.android.server.wm.proto.WindowStateProto.SURFACE_INSETS;
+import static com.android.server.wm.proto.WindowStateProto.WINDOW_CONTAINER;
 
+import android.annotation.CallSuper;
 import android.app.AppOpsManager;
 import android.content.Context;
 import android.content.res.Configuration;
@@ -3124,8 +3126,11 @@
                 || (isChildWindow() && getParentWindow().isDockedResizing());
     }
 
-    void writeToProto(ProtoOutputStream proto, long fieldId) {
+    @CallSuper
+    @Override
+    public void writeToProto(ProtoOutputStream proto, long fieldId) {
         final long token = proto.start(fieldId);
+        super.writeToProto(proto, WINDOW_CONTAINER);
         writeIdentifierToProto(proto, IDENTIFIER);
         proto.write(DISPLAY_ID, getDisplayId());
         proto.write(STACK_ID, getStackId());
diff --git a/services/core/java/com/android/server/wm/WindowToken.java b/services/core/java/com/android/server/wm/WindowToken.java
index 422615b..943448e 100644
--- a/services/core/java/com/android/server/wm/WindowToken.java
+++ b/services/core/java/com/android/server/wm/WindowToken.java
@@ -16,6 +16,7 @@
 
 package com.android.server.wm;
 
+import android.annotation.CallSuper;
 import android.util.proto.ProtoOutputStream;
 import java.util.Comparator;
 import static android.view.WindowManager.LayoutParams.FLAG_SHOW_WALLPAPER;
@@ -28,6 +29,7 @@
 import static com.android.server.wm.WindowManagerService.UPDATE_FOCUS_NORMAL;
 import static com.android.server.wm.proto.WindowTokenProto.HASH_CODE;
 import static com.android.server.wm.proto.WindowTokenProto.WINDOWS;
+import static com.android.server.wm.proto.WindowTokenProto.WINDOW_CONTAINER;
 
 import android.os.Debug;
 import android.os.IBinder;
@@ -263,8 +265,11 @@
         super.onDisplayChanged(dc);
     }
 
-    void writeToProto(ProtoOutputStream proto, long fieldId) {
+    @CallSuper
+    @Override
+    public void writeToProto(ProtoOutputStream proto, long fieldId) {
         final long token = proto.start(fieldId);
+        super.writeToProto(proto, WINDOW_CONTAINER);
         proto.write(HASH_CODE, System.identityHashCode(this));
         for (int i = 0; i < mChildren.size(); i++) {
             final WindowState w = mChildren.get(i);