Revert 128696 - roll clang 151385:153254 due to mac sizes regression

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 2034 matching lines @@
               '-Wno-c++11-extensions',
 
               # 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',
 
               # TODO(thakis): Reenable once this no longer complains about
               # Invalid() in gmocks's gmock-internal-utils.h
               # http://crbug.com/111806
               '-Wno-null-dereference',
-
-              # TODO(thakis): Investigate if it's worth cleaning up the code
-              # and turning this on.
-              '-Wno-null-conversion',
             ],
             'cflags!': [
               # Clang doesn't seem to know know this flag.
               '-mfpmath=sse',
             ],
           }],
           ['clang==1 and clang_use_chrome_plugins==1', {
             'cflags': [
               '<(clang_chrome_plugins_flags)',
             ],
@@ skipping 399 matching lines @@
                 '-Wno-c++11-extensions',
 
                 # 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',
 
                 # TODO(thakis): Reenable once this no longer complains about
                 # Invalid() in gmock's gmock-internal-utils.h
                 # http://crbug.com/111806
                 '-Wno-null-dereference',
-
-                # TODO(thakis): Investigate if it's worth cleaning up the code
-                # and turning this on.
-                '-Wno-null-conversion',
               ],
             }],
             ['clang==1 and clang_use_chrome_plugins==1', {
               'OTHER_CFLAGS': [
                 '<(clang_chrome_plugins_flags)',
               ],
             }],
             ['clang==1 and clang_load!=""', {
               'OTHER_CFLAGS': [
                 '-Xclang', '-load', '-Xclang', '<(clang_load)',
@@ skipping 459 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',
   },
 }