pepper: parse context creation attrib list on the plugin side

ppapi/thunk/resource_creation_api.h

Index: ppapi/thunk/resource_creation_api.h
diff --git a/ppapi/thunk/resource_creation_api.h b/ppapi/thunk/resource_creation_api.h
index 5636b5f4315f6eead8e9db06f925f070e8427b64..ae6dae6dd2a747cb609bfdae1cb2cee0c1d1a175 100644
--- a/ppapi/thunk/resource_creation_api.h
+++ b/ppapi/thunk/resource_creation_api.h
@@ -36,6 +36,9 @@ struct PP_NetAddress_Private;
 struct PP_Size;
 
 namespace gpu {
+namespace gles2 {
+struct ContextCreationAttribHelper;
+}
 struct Capabilities;
 }
 
@@ -142,7 +145,7 @@ class ResourceCreationAPI {
   virtual PP_Resource CreateGraphics3DRaw(
       PP_Instance instance,
       PP_Resource share_context,
-      const int32_t* attrib_list,
+      const gpu::gles2::ContextCreationAttribHelper& attrib_helper,
       gpu::Capabilities* capabilities,
       base::SharedMemoryHandle* shared_state,
       gpu::CommandBufferId* command_buffer_id) = 0;