Merge changes from topic 'shadowweather' into ub-launcher3-master

* changes:
  Adding ability to set a custom blur mask filter and alphas in shadow generator. am: 665971c007 am: fdf394e284
  Adding ability to set a custom blur mask filter and alphas in shadow generator. am: 665971c007
  Adding ability to set a custom blur mask filter and alphas in shadow generator.