Remove -Wa,--noexecstack flag on Android.

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 4670 matching lines @@
             'cflags!': [
               '-pthread',  # Not supported by Android toolchain.
             ],
             'cflags': [
               '-ffunction-sections',
               '-funwind-tables',
               '-g',
               '-fstack-protector',
               '-fno-short-enums',
               '-finline-limit=64',
-              '-Wa,--noexecstack',
               '<@(release_extra_cflags)',
               '--sysroot=<(android_ndk_sysroot)',
               # NOTE: The stlport header include paths below are specified in
               # cflags rather than include_dirs because they need to come
               # after include_dirs.
               # The include ordering here is important; change with caution.
               '-isystem<(android_stlport_include)',
             ],
             'defines': [
               'ANDROID',
@@ skipping 1398 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',
   },
 }