Downscale large bitmaps in CachingIconView

CachingIconView is used to displayed (smallish) icons in Notifications. Those can accidentally be made very large if big resources are used.
This makes CachingIconView use LocalImageResolver to load those images with limited size. This fixes large memory use of notification header icons.

Bug: 210690571
Bug: 218845090

Test: Manually on small and large Pixel device with Notification tester APK
      Added Unit Tests to cover this case.
Change-Id: If3d871e788608c1702461d563673560fa18fc53f