Remove reference to system theme

This change also introduces
 * Background for space key preview
 * Tune stone theme

Change-Id: I84fca0baf2392582da870d2ff77b3e99c28faf7b
30 files changed
tree: c119b3462dda11d4efbd7479afbeb8beb5964207
  1. dictionaries/
  2. java/
  3. native/
  4. tests/
  5. tools/
  6. Android.mk
  7. CleanSpec.mk