Roll Chromium 134666:140240.

This brings in a common.gypi change which enables warnings-as-errors on
Mac. Necessitated some modifications to third-party gyps.

BUG=none
TEST=trybots

Review URL: https://webrtc-codereview.appspot.com/618004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@2361 4adac7df-926f-26a2-2b94-8c16560cd09d

third_party/google-gflags/google-gflags.gyp

@@ -56,6 +56,11 @@
             'src/windows/port.cc',
           ],
         }],
+        ['OS=="mac" and clang==1', {
+          'xcode_settings': {
+            'WARNING_CFLAGS!': ['-Wheader-hygiene'],
+          },
+        }],
       ],
     },
   ],

third_party/libvpx/libvpx.gyp

@@ -7,6 +7,21 @@
 # libvpx_include, libvpx_lib.
 # http://src.chromium.org/svn/trunk/deps/third_party/libvpx/libvpx.gyp
 {
+  # The target_defaults block is unique to the WebRTC libvpx.gyp.
+  'target_defaults': {
+    'conditions': [
+      ['OS=="mac"', {
+        'xcode_settings': {
+          'WARNING_CFLAGS': [
+            '-Wno-implicit-function-declaration',
+            # TODO(andrew): this one should be fixed upstream.
+            '-Wno-parentheses-equality',
+            '-Wno-conversion',
+          ],
+        },
+      }],
+    ],
+  },
   'variables': {
     'conditions': [
       ['os_posix==1', {