Revert of Mojo bindings environment: remove usage in gles2.

mojo/gles2/command_buffer_client_impl.h

Index: mojo/gles2/command_buffer_client_impl.h
diff --git a/mojo/gles2/command_buffer_client_impl.h b/mojo/gles2/command_buffer_client_impl.h
index 995ff1c9511950c73155eb23800a3f548585176e..473c228c77d70075654135d170b2585c13d135e3 100644
--- a/mojo/gles2/command_buffer_client_impl.h
+++ b/mojo/gles2/command_buffer_client_impl.h
@@ -41,6 +41,7 @@
   explicit CommandBufferClientImpl(
       CommandBufferDelegate* delegate,
       const std::vector<int32_t>& attribs,
+      const MojoAsyncWaiter* async_waiter,
       mojo::ScopedMessagePipeHandle command_buffer_handle);
   ~CommandBufferClientImpl() override;
 
@@ -114,6 +115,8 @@
 
   uint64_t next_fence_sync_release_;
   uint64_t flushed_fence_sync_release_;
+
+  const MojoAsyncWaiter* async_waiter_;
 };
 
 }  // gles2