[Android] Workaround of an android platform bug.

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 2028 matching lines @@
       # section, and will not have access to the default fallback value of
       # chromium_code at the top of this file, or to the chromium_code
       # variable placed at the root variables scope of .gyp files, because
       # those variables are not set at target scope.  As a workaround,
       # if chromium_code is not set at target scope, define it in target scope
       # to contain whatever value it has during early variable expansion.
       # That's enough to make it available during target conditional
       # processing.
       'chromium_code%': '<(chromium_code)',
 
+      'component%': '<(component)',

[klobag.chromium, 2014/03/19 17:23:46]

why need this?

[Feng Qian, 2014/03/19 17:52:51]

gyp target_conditions has its own variable scope. Without definition here, we
cannot use 'component' in target_conditions. See clank-side change, line 95:
https://chrome-internal-review.googlesource.com/#/c/156166/8/native/framework...

+
       # See http://msdn.microsoft.com/en-us/library/aa652360(VS.71).aspx
       'win_release_Optimization%': '2', # 2 = /Os
       'win_debug_Optimization%': '0',   # 0 = /Od
 
       # See http://msdn.microsoft.com/en-us/library/2kxx5t2c(v=vs.80).aspx
       # Tri-state: blank is default, 1 on, 0 off
       'win_release_OmitFramePointers%': '0',
       # Tri-state: blank is default, 1 on, 0 off
       'win_debug_OmitFramePointers%': '',
 
@@ skipping 2999 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',
   },
 }