[Android][Tizen] Generate error messages from network error code.

Generate detailed error message from network error code.
For Android, it will popup a dialog contains the error message.

TODO:
1) The error page is not supported currently.
   Check whether it's needed in runtime.
2) The translations in grd file are missed.

BUG=XWALK-1274
Merge pull request #1766 from kurli/http-error

[Android][Tizen] Generate error messages from network error code.