Supress the two noisiest warnings on linux standalone builds.

build/standalone.gypi

 # Copyright 2014 PDFium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # Definitions to be used when building stand-alone PDFium binaries.
 
 {
   'variables': {
     'component%': 'static_library',
     'clang%': 0,
@@ skipping 126 matching lines @@
         'msvs_configuration_platform': 'x64',
       },
       'Release_x64': {
         'inherit_from': ['Release'],
         'msvs_configuration_platform': 'x64',
       },
     },
     'cflags': [
       '-Wall',
       '-W',
+      '-Wno-missing-field-initializers',
+      # Code might someday be made clean for -Wsign-compare, but for now
+      # this produces too much noise to be useful.
+      '-Wno-sign-compare',
       '-Wno-unused-parameter',
       '-pthread',
       '-fno-exceptions',
       '-fvisibility=hidden',
     ],
     'cflags_cc': [
       '-std=gnu++0x',
       '-Wnon-virtual-dtor',
       '-fno-rtti',
     ],
@@ skipping 116 matching lines @@
           'V8_USE_EXTERNAL_STARTUP_DATA',
         ],
       },
     }],  # v8_use_external_startup_data==1
   ],
   'xcode_settings': {
     # See comment in Chromium's common.gypi for why this is needed.
     'SYMROOT': '<(DEPTH)/xcodebuild',
   }
 }