Revert of command_buffer_gles2: Implement EGL default Display as a global object

gpu/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.
 
 # GYP-to-GN project mappings:
 #
 #  gpu.gyp:command_buffer_client => //gpu/command_buffer/client
 #
 #  gpu.gyp:command_buffer_common => //gpu/command_buffer/common
 #
@@ skipping 39 matching lines @@
     "//gpu/ipc/service:ipc_service_sources",
   ]
 }
 
 # GYP version: //gpu/gpu.gyp:command_buffer_gles2
 shared_library("command_buffer_gles2") {
   sources = [
     # TODO(hendrikw): Move egl out of gles2_conform_support.
     "gles2_conform_support/egl/config.cc",
     "gles2_conform_support/egl/config.h",
-    "gles2_conform_support/egl/context.cc",
-    "gles2_conform_support/egl/context.h",
     "gles2_conform_support/egl/display.cc",
     "gles2_conform_support/egl/display.h",
     "gles2_conform_support/egl/egl.cc",
     "gles2_conform_support/egl/surface.cc",
     "gles2_conform_support/egl/surface.h",
     "gles2_conform_support/egl/test_support.cc",
     "gles2_conform_support/egl/test_support.h",
-    "gles2_conform_support/egl/thread_state.cc",
-    "gles2_conform_support/egl/thread_state.h",
   ]
 
   deps = [
     ":gpu",
     "//base",
     "//gpu/command_buffer/client:gles2_c_lib",
     "//gpu/command_buffer/client:gles2_implementation",
-    "//gpu/command_buffer/common:gles2_utils",
     "//ui/gl:gl",
   ]
 
   defines = [
     "COMMAND_BUFFER_GLES_LIB_SUPPORT_ONLY",
     "EGLAPIENTRY=",
   ]
   if (current_os == "win") {
     defines += [ "EGLAPI=__declspec(dllexport)" ]
   } else {
@@ skipping 292 matching lines @@
     "//base",
     "//base/test:test_support",
     "//gpu/command_buffer/service",
     "//testing/gmock",
     "//testing/gtest",
     "//testing/perf",
     "//ui/gfx/geometry",
     "//ui/gl",
   ]
 }