diff --git a/core/java/android/view/IDisplayMagnificationMediator.aidl b/core/java/android/view/IDisplayMagnificationMediator.aidl
deleted file mode 100644
index aa25dac..0000000
--- a/core/java/android/view/IDisplayMagnificationMediator.aidl
+++ /dev/null
@@ -1,31 +0,0 @@
-/*
-** Copyright 2012, 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.
-*/
-
-package android.view;
-
-import android.view.IDisplayMagnificationController;
-import android.view.MagnificationSpec;
-
-/**
- * {@hide}
- */
-interface IDisplayMagnificationMediator {
-    void addController(int displayId, in IDisplayMagnificationController controller);
-    void removeController(in IDisplayMagnificationController controller);
-    void setMagnificationSpec(in IDisplayMagnificationController controller,
-            in MagnificationSpec spec);
-    MagnificationSpec getCompatibleMagnificationSpec(in IBinder windowToken);
-}
diff --git a/core/java/android/view/IDisplayMagnificationController.aidl b/core/java/android/view/IMagnificationCallbacks.aidl
similarity index 86%
rename from core/java/android/view/IDisplayMagnificationController.aidl
rename to core/java/android/view/IMagnificationCallbacks.aidl
index efe2775..032d073 100644
--- a/core/java/android/view/IDisplayMagnificationController.aidl
+++ b/core/java/android/view/IMagnificationCallbacks.aidl
@@ -16,11 +16,13 @@
 
 package android.view;
 
+import android.graphics.Region;
+
 /**
  * {@hide}
  */
-oneway interface IDisplayMagnificationController {
-    void onMagnifedFrameChanged(int left, int top, int right, int bottom);
+oneway interface IMagnificationCallbacks {
+    void onMagnifedBoundsChanged(in Region bounds);
     void onRectangleOnScreenRequested(int left, int top, int right, int bottom);
     void onRotationChanged(int rotation);
     void onUserContextChanged();
diff --git a/core/java/android/view/IWindowManager.aidl b/core/java/android/view/IWindowManager.aidl
index 17f04e9..1ee2bb3 100644
--- a/core/java/android/view/IWindowManager.aidl
+++ b/core/java/android/view/IWindowManager.aidl
@@ -27,7 +27,7 @@
 import android.os.Bundle;
 import android.os.IRemoteCallback;
 import android.view.IApplicationToken;
-import android.view.IDisplayMagnificationMediator;
+import android.view.IMagnificationCallbacks;
 import android.view.IOnKeyguardExitResult;
 import android.view.IRotationWatcher;
 import android.view.IWindowSession;
@@ -226,11 +226,6 @@
     void setInputFilter(in IInputFilter filter);
 
     /**
-     * Gets the display magnification mediator.
-     */
-    IDisplayMagnificationMediator getDisplayMagnificationMediator();
-
-    /**
      * Gets the frame of a window given its token.
      */
     void getWindowFrame(IBinder token, out Rect outFrame);
@@ -245,4 +240,30 @@
      * credentials.
      */
     void showAssistant();
+
+    /**
+     * Sets the display magnification callbacks. These callbacks notify
+     * the client for contextual changes related to display magnification.
+     *
+     * @param callbacks The magnification callbacks.
+     */
+    void setMagnificationCallbacks(IMagnificationCallbacks callbacks);
+
+    /**
+     * Sets the magnification spec to be applied to all windows that can be
+     * magnified.
+     *
+     * @param spec The current magnification spec.
+     */
+    void setMagnificationSpec(in MagnificationSpec spec);
+
+    /**
+     * Gets the magnification spec for a window given its token. If the
+     * window has a compatibility scale it is also folded in the returned
+     * magnification spec.
+     *
+     * @param windowToken The unique window token.
+     * @return The magnification spec if such or null.
+     */
+    MagnificationSpec getCompatibleMagnificationSpecForWindow(in IBinder windowToken);
 }
diff --git a/core/java/android/view/MagnificationSpec.java b/core/java/android/view/MagnificationSpec.java
index 7fb5615..0ee6714 100644
--- a/core/java/android/view/MagnificationSpec.java
+++ b/core/java/android/view/MagnificationSpec.java
@@ -39,6 +39,9 @@
     }
 
     public void initialize(float scale, float offsetX, float offsetY) {
+        if (scale < 1) {
+            throw new IllegalArgumentException("Scale must be greater than or equal to one!");
+        }
         this.scale = scale;
         this.offsetX = offsetX;
         this.offsetY = offsetY;
diff --git a/core/java/android/view/Surface.java b/core/java/android/view/Surface.java
index f2c5eac..a972b75 100644
--- a/core/java/android/view/Surface.java
+++ b/core/java/android/view/Surface.java
@@ -812,6 +812,8 @@
      *
      * @param rotation The rotation.
      * @return The rotation symbolic name.
+     *
+     * @hide
      */
     public static String rotationToString(int rotation) {
         switch (rotation) {
diff --git a/core/java/android/view/WindowManagerPolicy.java b/core/java/android/view/WindowManagerPolicy.java
index 7bdb44c..47ef638 100644
--- a/core/java/android/view/WindowManagerPolicy.java
+++ b/core/java/android/view/WindowManagerPolicy.java
@@ -1134,4 +1134,23 @@
      * {@link android.content.Intent#ACTION_ASSIST}
      */
     public void showAssistant();
+
+    /**
+     * Returns whether a given window type can be magnified.
+     *
+     * @param windowType The window type.
+     * @return True if the window can be magnified.
+     */
+    public boolean canMagnifyWindow(int windowType);
+
+    /**
+     * Returns whether a given window type is considered a top level one.
+     * A top level window does not have a container, i.e. attached window,
+     * or if it has a container it is laid out as a top-level window, not
+     * as a child of its container.
+     *
+     * @param windowType The window type.
+     * @return True if the window is a top level one.
+     */
+    public boolean isTopLevelWindow(int windowType);
 }