Make ShaderTranslatorCache thread safe

gpu/command_buffer/tests/gl_manager.cc

Index: gpu/command_buffer/tests/gl_manager.cc
diff --git a/gpu/command_buffer/tests/gl_manager.cc b/gpu/command_buffer/tests/gl_manager.cc
index dc30f454f31d6c9667aba47aa9a1f1929351e469..473ac6f6d0b47161a8dc1f8c3ac88043cbbb2009 100644
--- a/gpu/command_buffer/tests/gl_manager.cc
+++ b/gpu/command_buffer/tests/gl_manager.cc
@@ -117,11 +117,13 @@ void GLManager::Initialize(const GLManager::Options& options) {
   attrib_helper.Serialize(&attribs);
 
   if (!context_group) {
-    context_group = new gles2::ContextGroup(mailbox_manager_.get(),
-                                            options.image_manager,
-                                            NULL,
-                                            NULL,
-                                            options.bind_generates_resource);
+    context_group =
+        new gles2::ContextGroup(mailbox_manager_.get(),
+                                options.image_manager,
+                                NULL,
+                                new gpu::gles2::ShaderTranslatorCache,
+                                NULL,
+                                options.bind_generates_resource);
   }
 
   decoder_.reset(::gpu::gles2::GLES2Decoder::Create(context_group));