[Android WebView] Implement Ubercomp for Render Thread support

android_webview/browser/deferred_gpu_command_service.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "android_webview/browser/deferred_gpu_command_service.h"
 
 #include "android_webview/browser/gl_view_renderer_manager.h"
 #include "android_webview/browser/shared_renderer_state.h"
 #include "content/public/browser/android/synchronous_compositor.h"
 #include "gpu/command_buffer/service/shader_translator_cache.h"
@@ skipping 23 matching lines @@
 ScopedAllowGL::~ScopedAllowGL() { allow_gl.Get().Set(false); }
 
 // static
 void DeferredGpuCommandService::SetInstance() {
   if (!g_service.Get()) {
     g_service.Get() = new DeferredGpuCommandService;
     content::SynchronousCompositor::SetGpuService(g_service.Get());
   }
 }
 
+// static
+DeferredGpuCommandService* DeferredGpuCommandService::GetInstance() {
+  DCHECK(g_service.Get().get());
+  return g_service.Get().get();
+}
+
 DeferredGpuCommandService::DeferredGpuCommandService() {}
 
 DeferredGpuCommandService::~DeferredGpuCommandService() {
   base::AutoLock lock(tasks_lock_);
   DCHECK(tasks_.empty());
 }
 
+// This method can be called on any thread.
 // static
-void DeferredGpuCommandService::RequestProcessGLOnUIThread() {
+void DeferredGpuCommandService::RequestProcessGL() {
   SharedRendererState* renderer_state =
       GLViewRendererManager::GetInstance()->GetMostRecentlyDrawn();
   if (!renderer_state) {
     LOG(ERROR) << "No hardware renderer. Deadlock likely";
     return;
   }
   renderer_state->ClientRequestDrawGL();
 }
 
 // Called from different threads!
 void DeferredGpuCommandService::ScheduleTask(const base::Closure& task) {
   {
     base::AutoLock lock(tasks_lock_);
     tasks_.push(task);
   }
   if (ScopedAllowGL::IsAllowed()) {
     RunTasks();
   } else {
-    RequestProcessGLOnUIThread();
+    // TODO(boliu): Improve this to avoid PostTask storm.
+    RequestProcessGL();
   }
 }
 
 void DeferredGpuCommandService::ScheduleIdleWork(
     const base::Closure& callback) {
   // TODO(sievers): Should this do anything?
 }
 
 bool DeferredGpuCommandService::UseVirtualizedGLContexts() { return true; }
 
@@ skipping 28 matching lines @@
 
 void DeferredGpuCommandService::AddRef() const {
   base::RefCountedThreadSafe<DeferredGpuCommandService>::AddRef();
 }
 
 void DeferredGpuCommandService::Release() const {
   base::RefCountedThreadSafe<DeferredGpuCommandService>::Release();
 }
 
 }  // namespace android_webview