GN: Fix up various gpu targets

gpu/command_buffer/client/BUILD.gn

 # Copyright (c) 2013 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.
 
 source_set("client") {
   sources = [
     "cmd_buffer_helper.cc",
     "cmd_buffer_helper.h",
     "fenced_allocator.cc",
     "fenced_allocator.h",
@@ skipping 139 matching lines @@
   sources = gles2_c_lib_source_files
   defines = [ "GLES2_C_LIB_IMPLEMENTATION" ]
 
   if (is_win) {
     # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
     cflags = [ "/wd4267" ]  # size_t to int truncation.
   }
 
   deps = [
     ":client",
-    ":gles2_implementation",
     "//base",
     "//base/third_party/dynamic_annotations",
     "//gpu/command_buffer/common",
   ]
 }