cc: Refactor ResourceProvider.

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 18f4e18ea96a347d43e7f667f2af1da430c3e038..70656a21cac4025d9f8931d8ff54389fda5ad220 100644
--- a/cc/trees/thread_proxy.cc
+++ b/cc/trees/thread_proxy.cc
@@ -25,8 +25,11 @@
 #include "cc/trees/blocking_task_runner.h"
 #include "cc/trees/layer_tree_host.h"
 #include "cc/trees/layer_tree_impl.h"
+#include "gpu/command_buffer/client/gles2_interface.h"
 #include "ui/gfx/frame_time.h"
 
+using gpu::gles2::GLES2Interface;
+
 namespace {
 
 // Measured in seconds.
@@ -1273,8 +1276,12 @@ void ThreadProxy::InitializeOutputSurfaceOnImplThread(
 void ThreadProxy::FinishGLOnImplThread(CompletionEvent* completion) {
   TRACE_EVENT0("cc", "ThreadProxy::FinishGLOnImplThread");
   DCHECK(IsImplThread());
-  if (impl().layer_tree_host_impl->resource_provider())
-    impl().layer_tree_host_impl->resource_provider()->Finish();
+  if (impl().layer_tree_host_impl->output_surface()->context_provider())
+    impl()
+        .layer_tree_host_impl->output_surface()
+        ->context_provider()
+        ->ContextGL()
+        ->Finish();
   completion->Signal();
 }