Make ShaderTranslatorCache thread safe

content/common/gpu/gpu_channel_manager.cc

Index: content/common/gpu/gpu_channel_manager.cc
diff --git a/content/common/gpu/gpu_channel_manager.cc b/content/common/gpu/gpu_channel_manager.cc
index 86ea2bf7de6ef5e59797c192213f808698e3d957..3f521b25bda8ad4c30c1f46a9b452aee48e2fa08 100644
--- a/content/common/gpu/gpu_channel_manager.cc
+++ b/content/common/gpu/gpu_channel_manager.cc
@@ -15,6 +15,7 @@
 #include "gpu/command_buffer/service/gpu_switches.h"
 #include "gpu/command_buffer/service/mailbox_manager.h"
 #include "gpu/command_buffer/service/memory_program_cache.h"
+#include "gpu/command_buffer/service/shader_translator_cache.h"
 #include "ui/gl/gl_bindings.h"
 #include "ui/gl/gl_share_group.h"
 
@@ -67,6 +68,13 @@ gpu::gles2::ProgramCache* GpuChannelManager::program_cache() {
   return program_cache_.get();
 }
 
+gpu::gles2::ShaderTranslatorCache*
+GpuChannelManager::shader_translator_cache() {
+  if (!shader_translator_cache_.get())
+    shader_translator_cache_ = new gpu::gles2::ShaderTranslatorCache;
+  return shader_translator_cache_.get();
+}
+
 void GpuChannelManager::RemoveChannel(int client_id) {
   Send(new GpuHostMsg_DestroyChannel(client_id));
   gpu_channels_.erase(client_id);