[Android] Specify version code/name for android outputs at gyp time

The version in AndroidManifest.xml has two parts:versionCode and versionName.
VersionCode is an increasing integer to identifing upgrade.
VersionName is a human readable string.

For xwalk, VERSION file should be the only place to maintain version.
So this patch removes the hard coding in AndroidManifest.xml.

Insteadly, version code and version name will be specified as parameters at
gyp time for android's ant action.

For versionCode, it's calculated through version.
The formula is:
versionCode = shift +
              patch * 10 +
              build * 1000 +
              (major+minor) * 100000
Shift is the configuration bit. Currently, 1 for x86, 2 for armv7 and 3 for arm.

runtime/android/runtimelib/AndroidManifest.xml

@@ -7,7 +7,6 @@
 -->
 
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    android:versionCode="1" android:versionName="1.29.3.0"
     package="org.xwalk.runtime.lib">
 
     <application android:name="org.xwalk.runtime.lib.RuntimeLibApplication"

tools/build/android/generate_version_code.py

@@ -0,0 +1,90 @@
+#!/usr/bin/env python
+# Copyright (c) 2009 The Chromium Authors. All rights reserved.
+# Copyright (c) 2013 Intel Corporation. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""
+VersionCode is needed for AndroidManifest.xml,
+
+This script will generate version code based on
+VERSION file for xwalk's runtime library apk.
+"""
+
+import optparse
+import sys
+
+def fetch_values_from_file(values_dict, file_name):
+  """
+  Fetches KEYWORD=VALUE settings from the specified file.
+
+  Everything to the left of the first '=' is the keyword,
+  everything to the right is the value.  No stripping of
+  white space, so beware.
+
+  The file must exist, otherwise you get the Python exception from open().
+  """
+  for line in open(file_name, 'r').readlines():
+    key, val = line.rstrip('\r\n').split('=', 1)
+    if key in ['MAJOR', 'MINOR', 'BUILD', 'PATCH']:
+      try:
+        values_dict[key] = int(val)
+      except ValueError:
+        return False
+  return True
+
+
+def calculate_version_code(values_dict, shift):
+  """
+  Version Code is calculated based on the four version integers.
+
+  Major is for crosswalk's large update, and minor is for based chromium.
+  Major and minor will always be increasing, so use the sum of them is
+  enough.
+  For each major and minor refresh, build will reset to 0. After that,
+  the build will be increasing for 6 weeks (12 weeks if we skip one upstream
+  beta rebasing), so 100 numbers for build are enough.
+  After we branch it from trunk, the patch will be increasing for the rest of
+  this branch's life, 100 numbers are also enough since it will last for most
+  24 weeks, but the version increasing will be much less frequent after branch
+  point.
+  Shift is the last bit for different configurations we want to upload to
+  PlayStore.
+  """
+  try:
+    major = values_dict['MAJOR']
+    minor = values_dict['MINOR']
+    build = values_dict['BUILD']
+    patch = values_dict['PATCH']
+    return (major + minor) * 100000 +\
+           build * 1000 +\
+           patch * 10 +\
+           shift
+  except KeyError:
+    return 0
+
+
+def main():
+  option_parser = optparse.OptionParser()
+
+  option_parser.add_option('--file', '-f', default='VERSION',
+      help='Path to the version file.')
+  option_parser.add_option('--shift', '-s', default=0, type='int',
+      help='Shift for different configurations, PlayStore '
+           'requires different version code for multiple apks')
+  options, _ = option_parser.parse_args()
+
+  versions = {}
+
+  version_code = 0
+  if fetch_values_from_file(versions, options.file):
+    version_code = calculate_version_code(versions, options.shift)
+  print '%d' % version_code
+  if version_code == 0:
+    return 1
+  else:
+    return 0    
+
+
+if __name__ == '__main__':
+  sys.exit(main())

xwalk.gyp

@@ -709,6 +709,23 @@
       ],
     }],  # OS=="mac"
     ['OS=="android"', {
+      'variables': {
+        'variables': {
+          'conditions': [
+            ['android_app_abi=="x86"', {
+              'version_code_shift%': 1,
+            }],
+            ['android_app_abi=="armeabi-v7a"', {
+              'version_code_shift%': 2,
+            }],
+            ['android_app_abi=="armeabi"', {
+              'version_code_shift%': 3,
+            }],
+          ], # conditions
+        },
+        'version_code_shift%': '<(version_code_shift)',
+        'xwalk_version_code': '<!(python tools/build/android/generate_version_code.py -f VERSION -s <(version_code_shift))',
+      },
       'includes': [
         '../build/all_android.gyp',
         'xwalk_android.gypi',

xwalk_android.gypi

@@ -117,6 +117,8 @@
           '<(PRODUCT_DIR)/xwalk_runtime_lib/assets/xwalk.pak',
         ],
         'asset_location': '<(ant_build_out)/xwalk_runtime_lib/assets',
+        'app_manifest_version_name': '<(xwalk_version)',
+        'app_manifest_version_code': '<(xwalk_version_code)',
       },
       'includes': ['../build/java_apk.gypi'],
     },