Add missing files/deps/defines

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",
     "gpu_control.h",
     "mapped_memory.cc",
     "mapped_memory.h",
     "ring_buffer.cc",
     "ring_buffer.h",
     "transfer_buffer.cc",
     "transfer_buffer.h",
   ]
 
+  defines = [ "GPU_IMPLEMENTATION" ]
+
   if (is_win) {
     # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
     cflags = [ "/wd4267" ]  # size_t to int truncation.
   }
 
   all_dependent_configs = [ "//third_party/khronos:khronos_headers" ]
 
   deps = [
     "//gpu/command_buffer/common",
   ]
 }
 
 source_set("gles2_cmd_helper") {
   sources = [
     "gles2_cmd_helper.cc",
     "gles2_cmd_helper.h",
     "gles2_cmd_helper_autogen.h",
   ]
 
+  defines = [ "GLES2_IMPL_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_c_lib_source_files = [
   "gles2_c_lib.cc",
@@ skipping 107 matching lines @@
   }
 
   deps = [
     ":client",
     "//base",
     "//base/third_party/dynamic_annotations",
     "//gpu/command_buffer/common",
   ]
 }