[Android] Make variable name consistent in generate_xwalk_core_library.py

It's mix using "dir", "directory" and "folder". Change all to
"dir" for consistency.
[SysApps][Android]Fix Issue: Error callback isn't triggered without SIM card.

When there is no SIM card, the onSmsSend put a error message and return. Thus,
the JS error callback won't be invoked. Simply removing the return will
resolve the issue, the error will be handled in MessagingReceiver and
send back to JS end.

BUG=XWALK-940
Merge pull request #1696 from wang16/use_dir

[Android] Make variable name consistent in generate_xwalk_core_library.p...
Merge pull request #1686 from shawngao5/XWALK-940-1

[SysApps][Android] Fix Issue: Error callback isn't triggered without SIM card.
[Runtime] Add manifest handler for widget packaged applications.

The CL parses manifest keys required by JavaScript widget interface,
and save mapped key value pairs in ManifestData, so that it can be read
by widget extension.

We can also extend this CL to validate the widget configuration keys in
future.
[Tizen][Runtime] Implement Widget API.

This commit supports Widget API on Tizen(exclude 'preferences' attribute).
The API provides application programming interfaces that enables ability
to access some of the metadata declared in a widget's configuration
document, such as 'name', 'author', 'description'.

Spec:
http://www.w3.org/TR/widgets-apis/#the-widget-interface

The 'preferences' attribute implementation will be provided later.
Add widget preference implementation.