Move GpuImpl into services/gles2

mojo/services/native_viewport/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("//build/config/ui.gni")
 import("//mojo/public/mojo_application.gni")
 
 if (is_android) {
   import("//build/config/android/config.gni")
   import("//build/config/android/rules.gni")
@@ skipping 19 matching lines @@
       "//mojo/public/cpp/bindings:bindings",
       "//mojo/services/public/interfaces/native_viewport",
       "//mojo/services/public/cpp/native_viewport:args",
       "//ui/gl",
     ]
   }
 }
 
 source_set("lib") {
   sources = [
-    "gpu_impl.cc",
-    "gpu_impl.h",
     "native_viewport_impl.cc",
     "native_viewport_impl.h",
     "platform_viewport.h",
     "platform_viewport_android.cc",
     "platform_viewport_android.h",
     "platform_viewport_mac.mm",
     "platform_viewport_headless.cc",
     "platform_viewport_headless.h",
     "platform_viewport_ozone.cc",
     "platform_viewport_stub.cc",
@@ skipping 47 matching lines @@
   } else {
     sources -= [ "platform_viewport_x11.cc" ]
   }
   
   if (is_win) {
     deps += [
       "//ui/platform_window/win",
     ]
   }
 }