Merge "WM: add missing plumbing for preferredMaxDisplayRefreshRate" into sc-dev am: 8dff5292 am: 6ca70115 am: e51a2f8e

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/15133561

Change-Id: Icb99e441b942901354b42b3659d2c0a9d6bf1ccb