Update WindowManager to output dumpsys in protobuf format

Implement enough functionality in protobuf dumpsys to replicate
old functionaltiy in android.server.cts.WindowManagerState

Test: cts-tradefed run commandAndExit cts-dev --module CtsWindowManagerHostTestCases
cts-tradefed run commandAndExit cts-dev --module CtsServicesHostTestCases
Change-Id: Ib527ab3f44620a08cf03b77c37c2bae883d90e13
diff --git a/services/core/java/com/android/server/wm/DockedStackDividerController.java b/services/core/java/com/android/server/wm/DockedStackDividerController.java
index 6b51455..2b45d67 100644
--- a/services/core/java/com/android/server/wm/DockedStackDividerController.java
+++ b/services/core/java/com/android/server/wm/DockedStackDividerController.java
@@ -34,6 +34,7 @@
 import static com.android.server.wm.WindowManagerDebugConfig.TAG_WM;
 import static com.android.server.wm.WindowManagerService.H.NOTIFY_DOCKED_STACK_MINIMIZED_CHANGED;
 import static com.android.server.wm.WindowManagerService.LAYER_OFFSET_DIM;
+import static com.android.server.wm.proto.DockedStackDividerControllerProto.MINIMIZED_DOCK;
 
 import android.content.Context;
 import android.content.res.Configuration;
@@ -42,6 +43,7 @@
 import android.os.RemoteException;
 import android.util.ArraySet;
 import android.util.Slog;
+import android.util.proto.ProtoOutputStream;
 import android.view.DisplayInfo;
 import android.view.IDockedStackListener;
 import android.view.animation.AnimationUtils;
@@ -919,4 +921,10 @@
             mDimLayer.printTo(prefix + "    ", pw);
         }
     }
+
+    void writeToProto(ProtoOutputStream proto, long fieldId) {
+        final long token = proto.start(fieldId);
+        proto.write(MINIMIZED_DOCK, mMinimizedDock);
+        proto.end(token);
+    }
 }