Merge "Prevent XML_GetBuffer signed integer overflow" into rvc-dev am: 87560075e3

Original change: https://googleplex-android-review.googlesource.com/c/platform/external/expat/+/18724849

Change-Id: If7997a89efbf18af868e5a85798620bdd2ed8dd3
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>