Clear animations in DisplayLists when done

The matrix calculated by Animations is pushed down to the native
DisplayList object, and is then used when the DL is issued to the
GL renderer. This works while the animation is running, but the end
of animations is not handled correctly. In particular, we never clear the
animation, so whatever the last frame of the animation calculated will
persist on that DisplayList object until it is recreated.

The fix is to note when we used to be animating and are no longer
doing so, taking that opportunity to push the cleared state down
to the DisplayList.

Issue #6448993 action bar -- including settings menu -- disappears on Nakasi

Change-Id: I73cdadaef40d87ccbc1beb02599c4d70506ea42b

Author: chethaase

core/java/android/view/GLES20DisplayList.java

@@ -131,7 +131,8 @@ public void setStaticMatrix(Matrix matrix) {
     @Override
     public void setAnimationMatrix(Matrix matrix) {
         try {
-            nSetAnimationMatrix(getNativeDisplayList(), matrix.native_instance);
+            nSetAnimationMatrix(getNativeDisplayList(),
+                    (matrix != null) ? matrix.native_instance : 0);
         } catch (IllegalStateException e) {
             // invalid DisplayList okay: we'll set current values the next time we render to it
         }

core/java/android/view/View.java

@@ -2128,6 +2128,13 @@ public class View implements Drawable.Callback, Drawable.Callback2, KeyEvent.Cal
      */
     static final int ACCESSIBILITY_STATE_CHANGED = 0x00000080 << IMPORTANT_FOR_ACCESSIBILITY_SHIFT;
 
+    /**
+     * Flag indicating that view has an animation set on it. This is used to track whether an
+     * animation is cleared between successive frames, in order to tell the associated
+     * DisplayList to clear its animation matrix.
+     */
+    static final int VIEW_IS_ANIMATING_TRANSFORM = 0x10000000;
+
     /* End of masks for mPrivateFlags2 */
 
     static final int DRAG_MASK = DRAG_CAN_ACCEPT | DRAG_HOVERED;
@@ -12764,16 +12771,27 @@ boolean draw(Canvas canvas, ViewGroup parent, long drawingTime) {
         if (a != null) {
             more = drawAnimation(parent, drawingTime, a, scalingRequired);
             concatMatrix = a.willChangeTransformationMatrix();
+            if (concatMatrix) {
+                mPrivateFlags2 |= VIEW_IS_ANIMATING_TRANSFORM;
+            }
             transformToApply = parent.mChildTransformation;
-        } else if (!useDisplayListProperties &&
-                (flags & ViewGroup.FLAG_SUPPORT_STATIC_TRANSFORMATIONS) != 0) {
-            final boolean hasTransform =
-                    parent.getChildStaticTransformation(this, parent.mChildTransformation);
-            if (hasTransform) {
-                final int transformType = parent.mChildTransformation.getTransformationType();
-                transformToApply = transformType != Transformation.TYPE_IDENTITY ?
-                        parent.mChildTransformation : null;
-                concatMatrix = (transformType & Transformation.TYPE_MATRIX) != 0;
+        } else {
+            if ((mPrivateFlags2 & VIEW_IS_ANIMATING_TRANSFORM) == VIEW_IS_ANIMATING_TRANSFORM &&
+                    mDisplayList != null) {
+                // No longer animating: clear out old animation matrix
+                mDisplayList.setAnimationMatrix(null);
+                mPrivateFlags2 &= ~VIEW_IS_ANIMATING_TRANSFORM;
+            }
+            if (!useDisplayListProperties &&
+                    (flags & ViewGroup.FLAG_SUPPORT_STATIC_TRANSFORMATIONS) != 0) {
+                final boolean hasTransform =
+                        parent.getChildStaticTransformation(this, parent.mChildTransformation);
+                if (hasTransform) {
+                    final int transformType = parent.mChildTransformation.getTransformationType();
+                    transformToApply = transformType != Transformation.TYPE_IDENTITY ?
+                            parent.mChildTransformation : null;
+                    concatMatrix = (transformType & Transformation.TYPE_MATRIX) != 0;
+                }
             }
         }