Add ability to decode only image information with ImageDecoder

This creates a @hide API which only retrieves ImageInfo object without
continuing the decode of full image. It mirrors
BitmapOptions.inJustDecodeBounds behaviour and allows checking
dimensions and color space configuration of images without proceeding to
full decode (if able).

Bug: 280572656
Test: atest android.graphics.ImageDecoderTest
       android.graphics.cts.ImageDecoderTest
Change-Id: I704ec6c41d76f655222da7ee322e3b0e4954533d
3 files changed