DO NOT MERGE: fix for the XPath nodeTab use-after-free bug from nmehta@ am: 01ad0c65b5 am: 6321519b3b am: 6188da583e  -s ours am: a3da3e0a53  -s ours am: b8d635fa9e am: 368f921e0d  -s ours am: 981a28ea56 am: 38ae5ff712 am: 4a9e85f6ae am: b47b07cd6b  -s ours am: d5b161605e am: da50e0deb1 am: 2c4f74390d am: 0d760d8caf am: 5bc0b2aab8 am: 324f03a4c1  -s ours
am: dcf6483aba

Change-Id: Iac5e47933f24d7b8a0b9c329128fd17af99d844f