Migrate tint caching to ResourceManager

This patch moves the responsibility of tracking which tints are used
in a frame to the ResourceManager. When a tinted resource is requested
the ResourceManager tracks it instead of the TabListSceneLayer. When
a frame is finalized, the CompositorView passes a signal to the
ResourceManager to clear out any tinted resources that were not used
in that frame.

Bug: 1111772
Change-Id: I6f71aca94f1f05d413a4b3d0e83c39f11c4b7594
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2334992Reviewed-by: David Trainor <dtrainor@chromium.org>
Commit-Queue: Matthew Jones <mdjones@chromium.org>
Cr-Commit-Position: refs/heads/master@{#795434}

chrome/browser/android/compositor/compositor_view.cc

@@ -299,6 +299,8 @@ void CompositorView::SetSceneLayer(JNIEnv* env,
 
 void CompositorView::FinalizeLayers(JNIEnv* env,
                                     const JavaParamRef<jobject>& jobj) {
+  if (GetResourceManager())
+    GetResourceManager()->OnFrameUpdatesFinished();
 #if !defined(OFFICIAL_BUILD)
   TRACE_EVENT0("compositor", "CompositorView::FinalizeLayers");
 #endif

chrome/browser/android/compositor/scene_layer/tab_list_scene_layer.cc

@@ -42,8 +42,6 @@ void TabListSceneLayer::BeginBuildingFrame(JNIEnv* env,
   // matches PutTabLayer call order.
   for (auto tab : tab_map_)
     tab.second->layer()->RemoveFromParent();
-
-  used_tints_.clear();
 }
 
 void TabListSceneLayer::FinishBuildingFrame(JNIEnv* env,
@@ -57,8 +55,6 @@ void TabListSceneLayer::FinishBuildingFrame(JNIEnv* env,
       ++it;
   }
   visible_tabs_this_frame_.clear();
-  DCHECK(resource_manager_);
-  resource_manager_->RemoveUnusedTints(used_tints_);
 }
 
 void TabListSceneLayer::UpdateLayer(
@@ -149,13 +145,6 @@ void TabListSceneLayer::PutTabLayer(
   own_tree_->AddChild(layer->layer());
   visible_tabs_this_frame_.insert(id);
 
-  // Add the tints for the border asset and close icon to the list that was
-  // used for this frame.
-  used_tints_.insert(toolbar_background_color);
-  used_tints_.insert(close_button_color);
-  used_tints_.insert(default_theme_color);
-  used_tints_.insert(toolbar_textbox_background_color);
-
   DCHECK(layer);
   if (layer) {
     std::vector<int> tab_ids;

chrome/browser/android/compositor/scene_layer/tab_list_scene_layer.h

@@ -8,7 +8,6 @@
 #include <map>
 #include <memory>
 #include <set>
-#include <unordered_set>
 
 #include "base/macros.h"
 #include "cc/layers/layer.h"
@@ -121,9 +120,6 @@ class TabListSceneLayer : public SceneLayer {
   SkColor GetBackgroundColor() override;
 
  private:
-  // The set of tint colors that were used for a frame.
-  std::unordered_set<int> used_tints_;
-
   typedef std::map<int, scoped_refptr<TabLayer>> TabMap;
   TabMap tab_map_;
   std::set<int> visible_tabs_this_frame_;

ui/android/resources/resource_manager.h

@@ -49,11 +49,6 @@ class UI_ANDROID_EXPORT ResourceManager {
   virtual Resource* GetStaticResourceWithTint(int res_id,
                                               SkColor tint_color) = 0;
 
-  // Remove tints that were unused in the current frame being built. This
-  // function takes a set |used_tints| and removes all the tints not in the set
-  // from the cache.
-  virtual void RemoveUnusedTints(const std::unordered_set<int>& used_tints) = 0;
-
   // Trigger asynchronous loading of the resource specified by |res_type| and
   // |res_id|, if it has not yet been loaded.
   virtual void PreloadResource(AndroidResourceType res_type, int res_id) = 0;
@@ -65,6 +60,9 @@ class UI_ANDROID_EXPORT ResourceManager {
                                                : 0;
   }
 
+  // A notification that all updates have finished for the current frame.
+  virtual void OnFrameUpdatesFinished() = 0;
+
  protected:
   virtual ~ResourceManager() {}
 };

ui/android/resources/resource_manager_impl.cc

@@ -117,24 +117,30 @@ Resource* ResourceManagerImpl::GetResource(AndroidResourceType res_type,
   return item->second.get();
 }
 
-void ResourceManagerImpl::RemoveUnusedTints(
-    const std::unordered_set<int>& used_tints) {
+void ResourceManagerImpl::RemoveUnusedTints() {
   // Iterate over the currently cached tints and remove ones that were not
   // used as defined in |used_tints|.
   for (auto it = tinted_resources_.cbegin(); it != tinted_resources_.cend();) {
-    if (used_tints.find(it->first) == used_tints.end()) {
-        it = tinted_resources_.erase(it);
+    if (used_tints_.find(it->first) == used_tints_.end()) {
+      it = tinted_resources_.erase(it);
     } else {
-        ++it;
+      ++it;
     }
   }
 }
 
+void ResourceManagerImpl::OnFrameUpdatesFinished() {
+  RemoveUnusedTints();
+  used_tints_.clear();
+}
+
 Resource* ResourceManagerImpl::GetStaticResourceWithTint(int res_id,
                                                          SkColor tint_color) {
   if (tinted_resources_.find(tint_color) == tinted_resources_.end()) {
     tinted_resources_[tint_color] = std::make_unique<ResourceMap>();
   }
+
+  used_tints_.insert(tint_color);
   ResourceMap* resource_map = tinted_resources_[tint_color].get();
 
   // If the resource is already cached, use it.

ui/android/resources/resource_manager_impl.h

@@ -39,8 +39,8 @@ class UI_ANDROID_EXPORT ResourceManagerImpl
   Resource* GetResource(AndroidResourceType res_type, int res_id) override;
   Resource* GetStaticResourceWithTint(
       int res_id, SkColor tint_color) override;
-  void RemoveUnusedTints(const std::unordered_set<int>& used_tints) override;
   void PreloadResource(AndroidResourceType res_type, int res_id) override;
+  void OnFrameUpdatesFinished() override;
 
   // Called from Java
   // ----------------------------------------------------------
@@ -73,6 +73,11 @@ class UI_ANDROID_EXPORT ResourceManagerImpl
   virtual void RequestResourceFromJava(AndroidResourceType res_type,
                                        int res_id);
 
+  // Remove tints that were unused in the current frame being built. This
+  // function takes a set |used_tints| and removes all the tints not in the set
+  // from the cache.
+  void RemoveUnusedTints();
+
   using ResourceMap = std::unordered_map<int, std::unique_ptr<Resource>>;
   using TintedResourceMap =
       std::unordered_map<SkColor, std::unique_ptr<ResourceMap>>;
@@ -81,6 +86,9 @@ class UI_ANDROID_EXPORT ResourceManagerImpl
   ResourceMap resources_[ANDROID_RESOURCE_TYPE_COUNT];
   TintedResourceMap tinted_resources_;
 
+  // The set of tints that are used for resources in the current frame.
+  std::unordered_set<int> used_tints_;
+
   base::android::ScopedJavaGlobalRef<jobject> java_obj_;
 
   DISALLOW_COPY_AND_ASSIGN(ResourceManagerImpl);