OSV-2021-235 Global-buffer-overflow in QSvgSwitch::draw

OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=29873 Crash type: Global-buffer-overflow READ 1 Crash state: QSvgSwitch::draw QSvgTinyDocument::draw QSvgTinyDocument::draw...