Add gdb script for android webview test shell

For the convenience of debugging android webview test shell

TEST=
BUG=

Review URL: https://chromiumcodereview.appspot.com/13888004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@194797 0039d316-1c4b-4281-b951-d872f2087c98

build/android/adb_gdb_android_webview_shell

+#!/bin/bash
+#
+# Copyright (c) 2013 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.
+#
+# Attach to or start a ContentShell process and debug it.
+# See --help for details.
+#
+PROGDIR=$(dirname "$0")
+export ADB_GDB_PROGNAME=$(basename "$0")
+export ADB_GDB_ACTIVITY=.AwShellActivity
+"$PROGDIR"/adb_gdb \
+    --program-name=AwShellApplication \
+    --package-name=org.chromium.android_webview.shell \
+    "$@"