Bug 834376 - Move Android Sync PNG files from drawable to drawable-mdpi. r=rnewman

--HG--
rename : mobile/android/base/resources/drawable/desktop.png => mobile/android/base/resources/drawable-mdpi/desktop.png
rename : mobile/android/base/resources/drawable/mobile.png => mobile/android/base/resources/drawable-mdpi/mobile.png
Bug 834386 - AboutHomeContent: Finalizing a Cursor that has not been deactivated or closed r=bnicholson