AndroidPlatform: Delete Crosswalk zip if failing to extract
AndroidPlatform: Delete Crosswalk zip if failing to extract

If opening a Crosswalk zip for extraction fails, delete the file
because it is truncated in all likelihood. Also prompt user to
try again, a fresh download will usually fix this.

Fixes https://crosswalk-project.org/jira/browse/XWALK-3798

baleboy/crosswalk-app-tools,davidmaxwaterman/crosswalk-app-tools,baleboy/crosswalk-app-tools,shawngao5/crosswalk-app-tools,crosswalk-project/crosswalk-app-tools,baleboy/crosswalk-app-tools,crosswalk-project/crosswalk-app-tools,shawngao5/crosswalk-app-tools,pozdnyakov/crosswalk-app-tools,crosswalk-project/crosswalk-app-tools,hgl888/crosswalk-app-tools,hgl888/crosswalk-app-tools,pozdnyakov/crosswalk-app-tools,davidmaxwaterman/crosswalk-app-tools