OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=68412
Crash type: Heap-buffer-overflow READ 1
Crash state:
GfxTilingPattern::scanXObjectForBlendMode
GfxTilingPattern::scanSoftMaskForBlendMode
GfxTilingPattern::scanExtGStateForBlendMode