[automerger skipped] Fix leakage of DisplayContent referenced from TransitionController am: 6c04f9b6 -s ours am: 732bbb20 -s ours am: d751bca5 -s ours

am skip reason: Merged-In I44e2a794981fc114ada0ce98cd2471adf623d856 with SHA-1 491914c1 is already in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/17061629

Change-Id: I36408f12476e575fd2c4107715621e7efaf3a31e