Merge "Add an isCheckpointing() binder call for adb remount." am: b50480bb96 am: 60e41b7084 am: 026ae1a9ac am: 3fe914dd6a

Original change: https://android-review.googlesource.com/c/platform/system/vold/+/1330854

Change-Id: I3d88a258147fcc3b454e339d081159d46bd6f982