Merge "Add synchronized to make sure data correctness" am: e50b18b0c6 am: 055310bc2f am: 88f5094c1b

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1433918

Change-Id: If99df2f7a3376e2514babf726e9f6ee73205c7f2