Fix for race in writeToParcel and unparcel

Don't access the parcelled data while it might be recycled
by another thread.

Also make a local reference of mMap, which could be modified
by another thread.

Bug: 33325384
Test: Hard to repro, so no test
Change-Id: I77f6545ac174236a3da69c0c0f3a01b2eda3f34b
1 file changed