Point to build requirements page when there is a dependency check failure.

Tools/Scripts/webkitpy/layout_tests/port/android.py

 # Copyright (C) 2012 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
 # copyright notice, this list of conditions and the following disclaimer
@@ skipping 394 matching lines @@
     # Avoid initializing the adb path [worker count]+1 times by storing it as a static member.
     _adb_path = None
 
     SUPPORTED_VERSIONS = ('android')
 
     FALLBACK_PATHS = {'icecreamsandwich': ['android'] + linux.LinuxPort.latest_platform_fallback_path()}
 
     # Android has aac and mp3 codecs built in.
     PORT_HAS_AUDIO_CODECS_BUILT_IN = True
 
+    BUILD_REQUIREMENTS_URL = 'https://code.google.com/p/chromium/wiki/AndroidBuildInstructions'
+
     def __init__(self, host, port_name, **kwargs):
         super(AndroidPort, self).__init__(host, port_name, **kwargs)
 
         self._operating_system = 'android'
         self._version = 'icecreamsandwich'
 
         self._host_port = factory.PortFactory(host).get('chromium', **kwargs)
         self._server_process_constructor = self._android_server_process_constructor
 
         if not self.get_option('disable_breakpad'):
@@ skipping 850 matching lines @@
         return command
 
     def _read_prompt(self, deadline):
         last_char = ''
         while True:
             current_char = self._server_process.read_stdout(deadline, 1)
             if current_char == ' ':
                 if last_char in ('#', '$'):
                     return
             last_char = current_char