Fix some issues of the permission dialog

- Change the visibility of the ImageView first. To avoid the size
  changed after the decoding is finished.
- Set the default gray color in ImageView to ease the transition.
- Disable all buttons after the user clicks the positive button.
- Set true to windowNoTitle to hide the activity title.

Bug: 151083848
Bug: 151734029
Test: manual with MediaProviderDialogsTool
Change-Id: I8dd7d260ad59132e06c8b2140abf3be4039b90ac
6 files changed