Unifies LayerTreeHost::SetNeedsUpdateLayers and SetNeedsAnimate -- V2

cc/trees/thread_proxy.cc

Index: cc/trees/thread_proxy.cc
diff --git a/cc/trees/thread_proxy.cc b/cc/trees/thread_proxy.cc
index 931923f225352e5e301785de9794bf0613533298..a33bd7a50b0f0c706a6c990eebaab0d3caa8ecd7 100644
--- a/cc/trees/thread_proxy.cc
+++ b/cc/trees/thread_proxy.cc
@@ -81,7 +81,7 @@ ThreadProxy::ThreadProxy(
     LayerTreeHost* layer_tree_host,
     scoped_refptr<base::SingleThreadTaskRunner> impl_task_runner)
     : Proxy(impl_task_runner),
-      animate_requested_(false),
+      update_requested_(false),
       commit_requested_(false),
       commit_request_sent_to_impl_thread_(false),
       created_offscreen_context_provider_(false),
@@ -350,24 +350,14 @@ const RendererCapabilities& ThreadProxy::GetRendererCapabilities() const {
   return renderer_capabilities_main_thread_copy_;
 }
 
-void ThreadProxy::SetNeedsAnimate() {
-  DCHECK(IsMainThread());
-  if (animate_requested_)
-    return;
-
-  TRACE_EVENT0("cc", "ThreadProxy::SetNeedsAnimate");
-  animate_requested_ = true;
-  can_cancel_commit_ = false;
-  SendCommitRequestToImplThreadIfNeeded();
-}
-
 void ThreadProxy::SetNeedsUpdateLayers() {
   DCHECK(IsMainThread());
 
-  if (commit_request_sent_to_impl_thread_)
+  if (update_requested_)
     return;
   TRACE_EVENT0("cc", "ThreadProxy::SetNeedsUpdateLayers");
 
+  update_requested_ = true;
   SendCommitRequestToImplThreadIfNeeded();
 }
 
@@ -785,10 +775,10 @@ void ThreadProxy::BeginMainFrame(
   commit_requested_ = true;
   commit_request_sent_to_impl_thread_ = true;
 
-  // On the other hand, the AnimationRequested flag needs to be cleared
-  // here so that any animation requests generated by the apply or animate
+  // On the other hand, the update_requested_ flag needs to be cleared
+  // here so that any update requests generated by the apply or animate
   // callbacks will trigger another frame.
-  animate_requested_ = false;
+  update_requested_ = false;
 
   if (!in_composite_and_readback_ && !layer_tree_host()->visible()) {
     commit_requested_ = false;
@@ -851,7 +841,8 @@ void ThreadProxy::BeginMainFrame(
   bool can_cancel_this_commit =
       can_cancel_commit_ &&
       !in_composite_and_readback_ &&
-      !evicted_ui_resources;
+      !evicted_ui_resources &&
+      !layer_tree_host()->next_commit_forces_redraw();
   can_cancel_commit_ = true;
 
   scoped_ptr<ResourceUpdateQueue> queue =
@@ -865,6 +856,17 @@ void ThreadProxy::BeginMainFrame(
 
   layer_tree_host()->WillCommit();
 
+  // Before calling animate, we set update_requested_ to false. If it is true
+  // now, it means SetNeedsUpdateLayers was called again. Depending on during
+  // which phase of the commit SetNeedsUpdateLayers was called,
+  // commit_request_sent_to_impl_thread_ may be already cleared or not.
+  // We call SetNeedsUpdateLayers here to make sure a commit always gets posted.
+  if (update_requested_) {
+    // Forces SetNeedsUpdateLayers to consider posting a commit task.
+    update_requested_ = false;
+    SetNeedsUpdateLayers();
+  }
+
   if (!updated && can_cancel_this_commit) {
     TRACE_EVENT0("cc", "EarlyOut_NoUpdates");
     bool did_handle = true;
@@ -882,16 +884,6 @@ void ThreadProxy::BeginMainFrame(
     return;
   }
 
-  // Before calling animate, we set animate_requested_ to false. If it is true
-  // now, it means SetNeedAnimate was called again, but during a state when
-  // commit_request_sent_to_impl_thread_ = true. We need to force that call to
-  // happen again now so that the commit request is sent to the impl thread.
-  if (animate_requested_) {
-    // Forces SetNeedsAnimate to consider posting a commit task.
-    animate_requested_ = false;
-    SetNeedsAnimate();
-  }
-
   scoped_refptr<ContextProvider> offscreen_context_provider;
   if (renderer_capabilities_main_thread_copy_.using_offscreen_context3d &&
       layer_tree_host()->needs_offscreen_context()) {