Make compile with gcc 4.7 work

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 4233 matching lines @@
           ['binutils_version>=223', {
             # Newer binutils don't set DT_RPATH unless you disable "new" dtags
             # and the new DT_RUNPATH doesn't work without --no-as-needed flag.
             # FIXME(mithro): Figure out the --as-needed/--no-as-needed flags
             # inside this file to allow usage of --no-as-needed and removal of
             # this flag.
             'ldflags': [
               '-Wl,--disable-new-dtags',
             ],
           }],
-          ['gcc_version>=48 and clang==0', {
+          ['gcc_version>=47 and clang==0', {
             'target_conditions': [
               ['_toolset=="target"', {
                 'cflags_cc': [
                   '-std=gnu++11',
                   # See comment for -Wno-c++11-narrowing.
                   '-Wno-narrowing',
                   # TODO(thakis): Remove, http://crbug.com/263960
                   '-Wno-literal-suffix',
                 ],
               }],
             ],
           }],
-          ['host_gcc_version>=48 and clang==0', {
+          ['host_gcc_version>=47 and clang==0', {
             'target_conditions': [
               ['_toolset=="host"', {
                 'cflags_cc': [
                   '-std=gnu++11',
                   # See comment for -Wno-c++11-narrowing.
                   '-Wno-narrowing',
                   # TODO(thakis): Remove, http://crbug.com/263960
                   '-Wno-literal-suffix',
                 ],
               }],
@@ skipping 1393 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',
   },
 }