Re-land^2 WebVR compositor bypass via BrowserMain context + mailbox

chrome/browser/android/vr_shell/BUILD.gn

 # Copyright 2016 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("//build/config/android/rules.gni")
 import("//chrome/common/features.gni")
 import("//testing/test.gni")
 
 assert(enable_webvr)
 
@@ skipping 30 matching lines @@
       "vr_math.cc",
       "vr_math.h",
       "vr_omnibox.cc",
       "vr_omnibox.h",
       "vr_shell.cc",
       "vr_shell.h",
       "vr_shell_delegate.cc",
       "vr_shell_delegate.h",
       "vr_shell_gl.cc",
       "vr_shell_gl.h",
+      "vr_shell_gpu_renderer.cc",
+      "vr_shell_gpu_renderer.h",
       "vr_shell_renderer.cc",
       "vr_shell_renderer.h",
       "vr_usage_monitor.cc",
       "vr_usage_monitor.h",
       "vr_web_contents_observer.cc",
       "vr_web_contents_observer.h",
     ]
 
     if (enable_vr_shell_ui_dev) {
       defines += [ "ENABLE_VR_SHELL_UI_DEV" ]
@@ skipping 45 matching lines @@
       ":vr_common",
       "//base/test:run_all_unittests",
       "//base/test:test_support",
       "//chrome/browser",
       "//testing/gtest",
       "//third_party/WebKit/public:blink",
       "//ui/gfx/geometry",
     ]
   }
 }