Remove redundant codepath for webgl api blocking

gpu/ipc/service/gpu_channel_manager.h

Index: gpu/ipc/service/gpu_channel_manager.h
diff --git a/gpu/ipc/service/gpu_channel_manager.h b/gpu/ipc/service/gpu_channel_manager.h
index 288e3b982ed7c0554d8ff0585deb9c083cbbe69e..9b39cda81be774e5079d9294317d4ab84e1933e9 100644
--- a/gpu/ipc/service/gpu_channel_manager.h
+++ b/gpu/ipc/service/gpu_channel_manager.h
@@ -107,6 +107,7 @@ class GPU_EXPORT GpuChannelManager {
   void RemoveChannel(int client_id);
 
   void LoseAllContexts();
+  void MaybeExitOnContextLost();
 
 #if defined(OS_MACOSX)
   void AddBufferPresentedCallback(int32_t routing_id,
@@ -146,6 +147,10 @@ class GPU_EXPORT GpuChannelManager {
   void DidAccessGpu();
 #endif
 
+  bool is_exiting_for_lost_context() {
+    return exiting_for_lost_context_;
+  }
+
  protected:
   virtual scoped_ptr<GpuChannel> CreateGpuChannel(
       int client_id,
@@ -215,6 +220,9 @@ class GPU_EXPORT GpuChannelManager {
   base::TimeTicks begin_wake_up_time_;
 #endif
 
+  // Set during intentional GPU process shutdown.
+  bool exiting_for_lost_context_;
+
   // Member variables should appear before the WeakPtrFactory, to ensure
   // that any WeakPtrs to Controller are invalidated before its members
   // variable's destructors are executed, rendering them invalid.