Fix getBitmapCrops(..., originalBitmap = true) API

Previous computation would compute the crops for the cropped bitmap,
then rescale them for the original bitmap via some getOriginalCropHints
method. However this is not great, if the sample size is large (e.g. 2),
the rounding errors from the cropped bitmaps will be multiplied and can
exceed 1, resulting in 2px rounding error for some tests on TV.

WallpaperManager CTS expects an error of at most 1px.

In the worst cases, getBitmapCrops could return a crop larger than the
original bitmap, which shouldn't happen after this CL.

Flag: android.app.fix_get_bitmap_crops
Bug: 384502688
Test: manual with logs
Test: atest WallpaperManagerTest

Change-Id: I8c0ed5c2f6fc864fa8ad0adab5c240b195423b4f