Merge "Build boot images in bootclasspath_fragment/platform_bootclasspath" am:...

Merge "Build boot images in bootclasspath_fragment/platform_bootclasspath" am: 4bbf45fa am: 748d9540 am: 57610650 am: 39ca8223

Original change: https://android-review.googlesource.com/c/platform/build/soong/+/1690884

Change-Id: Id038db44f77f5310cc00d787414bef7ab13f30f1