Bug 1382091 - Delete ImageKeys with ClearCachedResources r=nical

gfx/layers/wr/WebRenderBridgeChild.cpp

@@ -465,13 +465,13 @@ void
 WebRenderBridgeChild::BeginClearCachedResources()
 {
   mIsInClearCachedResources = true;
-  SendClearCachedResources();
 }
 
 void
 WebRenderBridgeChild::EndClearCachedResources()
 {
   ProcessWebRenderParentCommands();
+  SendClearCachedResources();
   mIsInClearCachedResources = false;
 }
 

gfx/layers/wr/WebRenderBridgeParent.cpp

@@ -846,11 +846,11 @@ WebRenderBridgeParent::RecvClearCachedResources()
   mCompositorBridge->ObserveLayerUpdate(GetLayersId(), GetChildLayerObserverEpoch(), false);
 
   // Clear resources
-  // XXX Can we clear more resources?
   ++mWrEpoch; // Update webrender epoch
   mApi->ClearRootDisplayList(wr::NewEpoch(mWrEpoch), mPipelineId);
   // Schedule composition to clean up Pipeline
   mCompositorScheduler->ScheduleComposition();
+  DeleteOldImages();
   // Remove animations.
   for (std::unordered_set<uint64_t>::iterator iter = mActiveAnimations.begin(); iter != mActiveAnimations.end(); iter++) {
     mAnimStorage->ClearById(*iter);

gfx/layers/wr/WebRenderLayerManager.cpp

@@ -630,18 +630,18 @@ WebRenderLayerManager::MakeSnapshotIfRequired(LayoutDeviceIntSize aSize)
 void
 WebRenderLayerManager::AddImageKeyForDiscard(wr::ImageKey key)
 {
-  mImageKeys.push_back(key);
+  mImageKeysToDelete.push_back(key);
 }
 
 void
 WebRenderLayerManager::DiscardImages()
 {
   if (WrBridge()->IPCOpen()) {
-    for (auto key : mImageKeys) {
+    for (auto key : mImageKeysToDelete) {
       WrBridge()->SendDeleteImage(key);
     }
   }
-  mImageKeys.clear();
+  mImageKeysToDelete.clear();
 }
 
 void
@@ -666,7 +666,7 @@ WebRenderLayerManager::DiscardLocalImages()
   // Removes images but doesn't tell the parent side about them
   // This is useful in empty / failed transactions where we created
   // image keys but didn't tell the parent about them yet.
-  mImageKeys.clear();
+  mImageKeysToDelete.clear();
 }
 
 void
@@ -764,6 +764,7 @@ WebRenderLayerManager::ClearCachedResources(Layer* aSubtree)
   } else if (mRoot) {
     ClearLayer(mRoot);
   }
+  DiscardImages();
   WrBridge()->EndClearCachedResources();
 }
 

gfx/layers/wr/WebRenderLayerManager.h

@@ -214,7 +214,7 @@ private:
 
 private:
   nsIWidget* MOZ_NON_OWNING_REF mWidget;
-  std::vector<wr::ImageKey> mImageKeys;
+  std::vector<wr::ImageKey> mImageKeysToDelete;
   nsTArray<uint64_t> mDiscardedCompositorAnimationsIds;
 
   /* PaintedLayer callbacks; valid at the end of a transaciton,