AndroidSDK: Use exec() instead of execFile()
AndroidSDK: Use exec() instead of execFile()

When invoking "ant" don't use execFile() as that doesn't work very
well on windows with batch files.

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