Use source rect hint from stopSwipePipToHome of home am: b845064759

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/27832198

Change-Id: I95abb0742a4b02c5ff6179dee4660bb70014c4cf
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>