Fix more warnings on linux

Source/config.gyp

 #
 # Copyright (C) 2013 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
@@ skipping 77 matching lines @@
           # Due to a bug in gcc arm, we get warnings about uninitialized
           # timesNewRoman.unstatic.3258 and colorTransparent.unstatic.4879.
           'cflags': ['-Wno-uninitialized'],
         }],
         ['OS=="mac"', {
           # TODO: Turn this on on all platforms, http://crbug.com/312287
           'variables': {
             'chromium_code': 1,
           },
         }],
+        ['OS=="linux"', {
+          'variables': {
+            'chromium_code': 1,
+          },
+          'cflags_cc': [
+            '-Wno-sign-compare',
+            '-Wno-unused-function',
+          ],
+        }],
         ['clang==1', {
           'cflags': ['-Wglobal-constructors'],
           'xcode_settings': {
             'WARNING_CFLAGS': ['-Wglobal-constructors'],
           },
         }],
       ],
     },
   },
   {
@@ skipping 11 matching lines @@
     ],
     'direct_dependent_settings': {
       'cflags!': ['-Wglobal-constructors'],
       'xcode_settings': {
         'WARNING_CFLAGS!': ['-Wglobal-constructors'],
       },
     },
   }
   ],
 }