Merge "Prevent XML_GetBuffer signed integer overflow" into qt-dev am: 517a01093c

Original change: https://googleplex-android-review.googlesource.com/c/platform/external/expat/+/18718601

Change-Id: Ie555145499e788a988800d95802831bd07bfe2eb
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>