Re-activate the -Wno-deprecated-register flag

build/common.gypi

 # Copyright (c) 2012 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.
 
 # IMPORTANT:
 # Please don't directly include this file if you are building via gyp_chromium,
 # since gyp_chromium is automatically forcing its inclusion.
 {
   # Variables expected to be overriden on the GYP command line (-D) or by
   # ~/.gyp/include.gypi.
@@ skipping 4135 matching lines @@
                 # which we no longer use. Check if it makes sense to remove
                 # this as well. http://crbug.com/316352
                 '-Wno-unneeded-internal-declaration',
 
                 # Warns on switches on enums that cover all enum values but
                 # also contain a default: branch. Chrome is full of that.
                 '-Wno-covered-switch-default',
 
                 # Warns when a const char[] is converted to bool.
                 '-Wstring-conversion',
+
+                # Clang considers the `register` keyword as deprecated, but
+                # e.g. code generated by flex (used in angle) contains that
+                # keyword. http://crbug.com/255186
+                '-Wno-deprecated-register',
               ],
 
               'conditions': [
                 ['clang_xcode==0', {
                   'CC': '$(SOURCE_ROOT)/<(clang_dir)/clang',
                   'LDPLUSPLUS': '$(SOURCE_ROOT)/<(clang_dir)/clang++',
-
-                  'WARNING_CFLAGS': [
-                    # Clang considers the `register` keyword as deprecated, but
-                    # e.g. code generated by flex (used in angle) contains that
-                    # keyword. http://crbug.com/255186
-                    #
-                    # Note: clang as shipped with Xcode is older and does not
-                    # treat the `register` as deprecated and does not define
-                    # this flag, so don't enable it if "clang_xcode" is "1".
-                    '-Wno-deprecated-register',
-                  ],
                 }],
               ],
             }],
             ['clang==1 and clang_xcode==0 and clang_use_chrome_plugins==1', {
               'OTHER_CFLAGS': [
                 '<@(clang_chrome_plugins_flags)',
               ],
             }],
             ['clang==1 and clang_xcode==0 and clang_load!=""', {
               'OTHER_CFLAGS': [
@@ skipping 869 matching lines @@
     # settings in target dicts.  SYMROOT is a special case, because many other
     # Xcode variables depend on it, including variables such as
     # PROJECT_DERIVED_FILE_DIR.  When a source group corresponding to something
     # like PROJECT_DERIVED_FILE_DIR is added to a project, in order for the
     # files to appear (when present) in the UI as actual files and not red
     # red "missing file" proxies, the correct path to PROJECT_DERIVED_FILE_DIR,
     # and therefore SYMROOT, needs to be set at the project level.
     'SYMROOT': '<(DEPTH)/xcodebuild',
   },
 }