Fix testUrl test case failed issue.

Add ErrorCodeConvertor for XWalk backend, because its error code is
different with Cordova error code.
Merge pull request #92 from junmin-zhu/testUrl

Fix testUrl test case failed issue.
Merge pull request #94 from wang16/xwalk

Fix that CordovaChromeClient misses all the implementation in xwalk
Fix that onNewIntent in CordovaWebView should return boolean as in XWalkView

onNewIntent in XWalkView is introduced by Notification API, it needs
return boolean to identify the intent is consumed or not.

BUG=https://crosswalk-project.org/jira/browse/XWALK-1072