Fix(?) Theme Tests

Bug 5404694

- ThemeTester and ActivitySnapshotTester were running into OOM errors.
  Add some bitmap.recycle() calls to fix these...

- ActivitySnapshotTester was hitting an infinite loop, because the
  decor view's width and height for dialog themes didn't match
  the reference width and height that seems to be sized like a
  regular activity. Furthermore, the resource width and height
  attributes are always negative, so they never match the the
  decor's dimensions. The width and height attributes being
  negative appears to occur in GB too, so I don't know how this
  could have worked or why it is there...

- Fixed the themetestscripts to only build what is necessary
  and pull the files into the CTS out directory.

  These scripts could be further improved to not require root
  by simply storing the files on external storage I think...

Change-Id: I1a699241690f3afe52c68017290c6caef8447d1d