Plumb client side synthesized GL messages to JS Console

gpu/command_buffer/client/gles2_implementation.h

Index: gpu/command_buffer/client/gles2_implementation.h
diff --git a/gpu/command_buffer/client/gles2_implementation.h b/gpu/command_buffer/client/gles2_implementation.h
index 2b5312a62451936a33c08954d84c8e9bfdb385a9..4e5334a8ca32510ab55f9ab83ef4febd577bf97d 100644
--- a/gpu/command_buffer/client/gles2_implementation.h
+++ b/gpu/command_buffer/client/gles2_implementation.h
@@ -108,6 +108,12 @@ class IdHandlerInterface {
 // shared memory and synchronization issues.
 class GLES2_IMPL_EXPORT GLES2Implementation {
  public:
+  class ErrorMessageCallback {
+   public:
+    virtual ~ErrorMessageCallback() { }
+    virtual void OnErrorMessage(const char* msg, int id) = 0;
+  };
+
   // Stores client side cached GL state.
   struct GLState {
     GLState()
@@ -215,6 +221,10 @@ class GLES2_IMPL_EXPORT GLES2Implementation {
   void FreeUnusedSharedMemory();
   void FreeEverything();
 
+  void SetErrorMessageCallback(ErrorMessageCallback* callback) {
+    error_message_callback_ = callback;
+  }
+
  private:
   friend class ClientSideBufferHelper;
   friend class GLES2ImplementationTest;
@@ -522,6 +532,8 @@ class GLES2_IMPL_EXPORT GLES2Implementation {
   scoped_ptr<QueryTracker> query_tracker_;
   QueryTracker::Query* current_query_;
 
+  ErrorMessageCallback* error_message_callback_;
+
   DISALLOW_COPY_AND_ASSIGN(GLES2Implementation);
 };