[automerger skipped] [DO NOT MERGE] Make GlobalScreenshot PendingIntents immutable am: bb4bfcc575 -s ours am: 57f5463b2a am: 5f3cb8f6e2 am: 4de3723c60 am: c18ca2dad9 -s ours

am skip reason: subject contains skip directive

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/12770654

Change-Id: I23163ad93a58eb3bdc111686ebfd3772abc11292