Unregister the ViewResourceAdapter for Grid Tab Switcher after animation

A ViewResourceAdapter is used to show the Grid Tab Switcher (GTS) in the
background when playing the Tab-to-Grid transition animation. After the
animation is done, the Java-side bitmap is released in
https://crrev.com/c/1636833 and https://crrev.com/c/1639150, but the
native-side bitmap is kept, wasting ~3MB of native memory on high-end
phones (assuming downsampling scale = 0.5).

The effects on performance (frame rate, max frame interval, etc) are
within error margin.

Bug: 971281
Change-Id: I9b29a91cb593c46505f1d2be29f7d3dd5e12feb6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1645458
Commit-Queue: Wei-Yin Chen (陳威尹) <wychen@chromium.org>
Reviewed-by: David Trainor <dtrainor@chromium.org>
Reviewed-by: Matthew Jones <mdjones@chromium.org>
Reviewed-by: Yusuf Ozuysal <yusufo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#669996}

chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/tab_management/TabListRecyclerView.java

@@ -86,7 +86,9 @@ class TabListRecyclerView extends RecyclerView {
     private ValueAnimator mFadeInAnimator;
     private ValueAnimator mFadeOutAnimator;
     private VisibilityListener mListener;
+    private DynamicResourceLoader mLoader;
     private ViewResourceAdapter mDynamicView;
+    private boolean mIsDynamicViewRegistered;
     private long mLastDirtyTime;
     private RecyclerView.ItemAnimator mOriginalAnimator;
     private ImageView mShadowImageView;
@@ -111,6 +113,8 @@ class TabListRecyclerView extends RecyclerView {
     void prepareOverview() {
         endAllAnimations();
 
+        registerDynamicView();
+
         // Stop all the animations to make all the items show up and scroll to position immediately.
         mOriginalAnimator = getItemAnimator();
         setItemAnimator(null);
@@ -142,8 +146,10 @@ class TabListRecyclerView extends RecyclerView {
                 // Restore the original value.
                 setItemAnimator(mOriginalAnimator);
                 setShadowVisibility(computeVerticalScrollOffset() > 0);
-                if (mDynamicView != null)
+                if (mDynamicView != null) {
                     mDynamicView.dropCachedBitmap();
+                    unregisterDynamicView();
+                }
             }
         });
         if (!animate) mFadeInAnimator.end();
@@ -214,7 +220,24 @@ class TabListRecyclerView extends RecyclerView {
             }
         };
         mDynamicView.setDownsamplingScale(getDownsamplingScale());
-        loader.registerResource(getResourceId(), mDynamicView);
+        assert mLoader == null : "createDynamicView should only be called once";
+        mLoader = loader;
+    }
+
+    private void registerDynamicView() {
+        if (mIsDynamicViewRegistered) return;
+        if (mLoader == null) return;
+
+        mLoader.registerResource(getResourceId(), mDynamicView);
+        mIsDynamicViewRegistered = true;
+    }
+
+    private void unregisterDynamicView() {
+        if (!mIsDynamicViewRegistered) return;
+        if (mLoader == null) return;
+
+        mLoader.unregisterResource(getResourceId());
+        mIsDynamicViewRegistered = false;
     }
 
     @SuppressLint("NewApi") // Used on O+, invalidateChildInParent used for previous versions.
@@ -264,6 +287,9 @@ class TabListRecyclerView extends RecyclerView {
      */
     void startHiding(boolean animate) {
         endAllAnimations();
+
+        registerDynamicView();
+
         mListener.startedHiding(animate);
         mFadeOutAnimator = ObjectAnimator.ofFloat(this, View.ALPHA, 0);
         mFadeOutAnimator.setInterpolator(BakedBezierInterpolator.FADE_OUT_CURVE);
@@ -284,6 +310,7 @@ class TabListRecyclerView extends RecyclerView {
     void postHiding() {
         if (mDynamicView != null) {
             mDynamicView.dropCachedBitmap();
+            unregisterDynamicView();
         }
     }
 

ui/android/java/src/org/chromium/ui/resources/ResourceLoader.java

@@ -16,25 +16,25 @@ public abstract class ResourceLoader {
         /**
          * Called when a resource as finished loading.  Note that it is up to the caller to recycle
          * any {@link android.graphics.Bitmap}s or clean up any state after making this call.
-         * @param resType  The {@link ResourceType} that loaded the resource.
+         * @param resType  The {@link AndroidResourceType} that loaded the resource.
          * @param resId    The Android id of the loaded resource.
          * @param resource The {@link Resource} of the resource, or {@code null} if one could
          *                 not be loaded.
          */
-        void onResourceLoaded(int resType, int resId, Resource resource);
+        void onResourceLoaded(@AndroidResourceType int resType, int resId, Resource resource);
 
         /**
          * Called when a resource is unregistered (unneeded). This should only be called for
-         * dynamic bitmap resources since they change constantly and are replaced with new bitmaps.
-         * Other resource types should not need this since thay are static for the lifetime of the
+         * dynamic resources. Dynamic bitmap change constantly and are replaced with new bitmaps.
+         * Other resource types should not need this since they are static for the lifetime of the
          * application.
-         * @param resType The {@link ResourceType} of resource that was removed.
-         * @param redId The Android id of the removed resource.
+         * @param resType The {@link AndroidResourceType} of resource that was removed.
+         * @param resId The Android id of the removed resource.
          */
-        void onResourceUnregistered(int resType, int resId);
+        void onResourceUnregistered(@AndroidResourceType int resType, int resId);
     }
 
-    private final int mResourceType;
+    private final @AndroidResourceType int mResourceType;
     private final ResourceLoaderCallback mCallback;
 
     /**
@@ -51,7 +51,7 @@ public abstract class ResourceLoader {
     /**
      * @return What resource type this {@link ResourceLoader} is responsible for loading.
      */
-    public int getResourceType() {
+    public @AndroidResourceType int getResourceType() {
         return mResourceType;
     }
 

ui/android/java/src/org/chromium/ui/resources/ResourceManager.java

@@ -122,14 +122,14 @@ public class ResourceManager implements ResourceLoaderCallback {
      * @param resId   The id of the Android resource.
      * @return The corresponding {@link LayoutResource}.
      */
-    public LayoutResource getResource(int resType, int resId) {
+    public LayoutResource getResource(@AndroidResourceType int resType, int resId) {
         SparseArray<LayoutResource> bucket = mLoadedResources.get(resType);
         return bucket != null ? bucket.get(resId) : null;
     }
 
     @SuppressWarnings("cast")
     @Override
-    public void onResourceLoaded(int resType, int resId, Resource resource) {
+    public void onResourceLoaded(@AndroidResourceType int resType, int resId, Resource resource) {
         if (resource == null) return;
         Bitmap bitmap = resource.getBitmap();
         if (bitmap == null) return;
@@ -144,9 +144,10 @@ public class ResourceManager implements ResourceLoaderCallback {
     }
 
     @Override
-    public void onResourceUnregistered(int resType, int resId) {
-        // Only remove dynamic bitmaps that were unregistered.
-        if (resType != AndroidResourceType.DYNAMIC_BITMAP) return;
+    public void onResourceUnregistered(@AndroidResourceType int resType, int resId) {
+        // Only remove dynamic resources that were unregistered.
+        if (resType != AndroidResourceType.DYNAMIC_BITMAP && resType != AndroidResourceType.DYNAMIC)
+            return;
 
         nativeRemoveResource(mNativeResourceManagerPtr, resType, resId);
     }
@@ -159,7 +160,8 @@ public class ResourceManager implements ResourceLoaderCallback {
         nativeClearTintedResourceCache(mNativeResourceManagerPtr);
     }
 
-    private void saveMetadataForLoadedResource(int resType, int resId, Resource resource) {
+    private void saveMetadataForLoadedResource(
+            @AndroidResourceType int resType, int resId, Resource resource) {
         SparseArray<LayoutResource> bucket = mLoadedResources.get(resType);
         if (bucket == null) {
             bucket = new SparseArray<LayoutResource>();