Update existing uses of /wd4267 to use the GN config

ui/base/ime/BUILD.gn

 # Copyright 2015 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("//testing/test.gni")
 
 component("ime") {
   output_name = "ui_base_ime"
   sources = [
@@ skipping 81 matching lines @@
     "text_input_focus_manager.cc",
     "text_input_focus_manager.h",
     "text_input_type.h",
     "ui_base_ime_export.h",
     "win/imm32_manager.cc",
     "win/imm32_manager.h",
     "win/tsf_input_scope.cc",
     "win/tsf_input_scope.h",
   ]
 
+  # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
+  configs += [ "//build/config/compiler:no_size_t_to_int_warning" ]
+
   defines = [ "UI_BASE_IME_IMPLEMENTATION" ]
 
   deps = [
     "//base",
     "//base/third_party/dynamic_annotations",
     "//base:i18n",
     "//net",
     "//third_party/icu",
     "//ui/base",
     "//ui/events",
@@ skipping 45 matching lines @@
       "composition_text_util_pango.h",
     ]
   }
   if (use_x11) {
     configs += [ "//build/config/linux:x11" ]
     deps += [ "//ui/gfx/x" ]
   }
 
   if (is_win) {
     cflags = [
-      "/wd4267",  # TODO(jschuh): C4267: http://crbug.com/167187 size_t -> int.
       "/wd4324",  # Structure was padded due to __declspec(align()), which is
                   # uninteresting.
     ]
     libs = [ "imm32.lib" ]
   }
 
   if (use_ozone) {
     deps += [
       "//ui/ozone",
       "//ui/events/ozone:events_ozone_layout",
     ]
   }
 }