Support custom creation of AFD for ImageDecoder.

ContentResolver.openTypedAssetFileDescriptor() has support for a
Bundle of options that can be used to communicate things like desired
thumbnail size, and also CancellationSignal to cancel large network
fetches when no longer needed.

Instead of adding all these to ImageDecoder, let developers provide
their own Callable<AssetFileDescriptor> so they can implement these
custom features.

Bug: 111268862
Test: atest cts/tests/tests/graphics/src/android/graphics/cts/ImageDecoderTest.java
Change-Id: I51c509962f50dd08be94507169355b5da54d6782