Use MailboxManagerSync on android.

services/gles2/BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//mojo/public/tools/bindings/mojom.gni")
 
 source_set("gles2") {
   visibility = [
     "//shell:parent_lib",  # For android
     "//services/native_viewport:*",
   ]
 
   sources = [
     "command_buffer_driver.cc",
     "command_buffer_driver.h",
     "command_buffer_impl.cc",
     "command_buffer_impl.h",
     "gpu_impl.cc",
     "gpu_impl.h",
     "gpu_state.cc",
     "gpu_state.h",
+    "mailbox_manager_factory.cc",
+    "mailbox_manager_factory.h",
   ]
 
   public_deps = [
     ":lib",
   ]
   deps = [
     "//base",
     "//gpu/command_buffer/service",
     "//mojo/converters/geometry",
     "//mojo/public/cpp/bindings",
@@ skipping 14 matching lines @@
   ]
 
   deps = [
     "//base",
     "//gpu/command_buffer/common",
     "//mojo/public/cpp/bindings",
     "//mojo/public/cpp/system",
     "//mojo/services/gpu/public/interfaces",
   ]
 }