Android: Implement support for extension permissions
Android: Implement support for extension permissions

BUG=XWALK-4021

baleboy/crosswalk-app-tools,crosswalk-project/crosswalk-app-tools,baleboy/crosswalk-app-tools,baleboy/crosswalk-app-tools,crosswalk-project/crosswalk-app-tools,crosswalk-project/crosswalk-app-tools