[automerge] Fix a bug when getting a gzip header extra field with inflate()....

[automerge] Fix a bug when getting a gzip header extra field with inflate(). 2p: 17292424 am: c362b4c0 am: 24ade941

Original change: https://googleplex-android-review.googlesource.com/c/platform/external/zlib/+/20545969



Change-Id: I3a7ec52496ed4cf2541e3bada833f6607c1f86dd
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>