Fixed race condition in Spinner.DialogPopup on null reference.

NullPointerException is triggered when DialogPopup is
dismissed due to object mPopup being null when not showing.
Race condition is triggered when dialog is dismissed before
touch event to dismiss dialog has been processed properly.

Fixed by adding a null check prior to accessing mPopup object.

Change-Id: I3c4fe9c279d92a7103fb4f68189d1d42beedc606
Missing break in switch statement

Change-Id: I462c0c5fec96a850032266b04419ec409ad02174
Fixed incorrect calculation of dirty invalidation area

Padding was already taken into consideration before calling
invalidateDrawable in ProgressBar.

Change-Id: I75f25b0b7ee87d394422c58888ed3a1cca5d06a8