Bug 934646 - Delete unused resources. r=mfinkle

These resources weren't defined in moz.build, so they were never
copied to $OBJDIR/mobile/android/base/res.  This means they could not
have been referenced by the system.  (Of course, text search turns up
zero uses as well.)
Bug 934646 - Replace hard-coded Android resource ID. r=mfinkle
Bug 934646 - Declare Android resource directories relative to $SRCDIR. r=glandium,gps,mfinkle

--HG--
rename : mobile/android/branding/aurora/content/fennec_72x72.png => mobile/android/branding/aurora/res/drawable-hdpi/icon.png
rename : mobile/android/branding/aurora/content/fennec_48x48.png => mobile/android/branding/aurora/res/drawable-mdpi/icon.png
rename : mobile/android/branding/aurora/content/fennec_96x96.png => mobile/android/branding/aurora/res/drawable-xhdpi/icon.png
rename : mobile/android/branding/aurora/content/fennec_144x144.png => mobile/android/branding/aurora/res/drawable-xxhdpi/icon.png
rename : mobile/android/branding/beta/content/fennec_72x72.png => mobile/android/branding/beta/res/drawable-hdpi/icon.png
rename : mobile/android/branding/beta/content/fennec_48x48.png => mobile/android/branding/beta/res/drawable-mdpi/icon.png
rename : mobile/android/branding/beta/content/fennec_96x96.png => mobile/android/branding/beta/res/drawable-xhdpi/icon.png
rename : mobile/android/branding/beta/content/fennec_144x144.png => mobile/android/branding/beta/res/drawable-xxhdpi/icon.png
rename : mobile/android/branding/nightly/content/fennec_72x72.png => mobile/android/branding/nightly/res/drawable-hdpi/icon.png
rename : mobile/android/branding/nightly/content/fennec_48x48.png => mobile/android/branding/nightly/res/drawable-mdpi/icon.png
rename : mobile/android/branding/nightly/content/fennec_96x96.png => mobile/android/branding/nightly/res/drawable-xhdpi/icon.png
rename : mobile/android/branding/nightly/content/fennec_144x144.png => mobile/android/branding/nightly/res/drawable-xxhdpi/icon.png
rename : mobile/android/branding/official/content/fennec_72x72.png => mobile/android/branding/official/res/drawable-hdpi/icon.png
rename : mobile/android/branding/official/content/fennec_48x48.png => mobile/android/branding/official/res/drawable-mdpi/icon.png
rename : mobile/android/branding/official/content/fennec_96x96.png => mobile/android/branding/official/res/drawable-xhdpi/icon.png
rename : mobile/android/branding/official/content/fennec_144x144.png => mobile/android/branding/official/res/drawable-xxhdpi/icon.png
rename : mobile/android/branding/unofficial/content/fennec_72x72.png => mobile/android/branding/unofficial/res/drawable-hdpi/icon.png
rename : mobile/android/branding/unofficial/content/fennec_48x48.png => mobile/android/branding/unofficial/res/drawable-mdpi/icon.png
rename : mobile/android/branding/unofficial/content/fennec_96x96.png => mobile/android/branding/unofficial/res/drawable-xhdpi/icon.png
rename : mobile/android/branding/unofficial/content/fennec_144x144.png => mobile/android/branding/unofficial/res/drawable-xxhdpi/icon.png