Fix memory leak caused by xr.

https://ci.chromium.org/p/chromium/builders/ci/WebKit%20Linux%20Trusty%20Leak/31116
[1/1] ar_hittest.html failed unexpectedly (leak detected: ({"numberOfLiveDocuments":[1,2],"numberOfLiveNodes":[4,36],"numberOfLiveResourceFetchers":[1,2],"numberOfLiveResources":[0,16]}))

Change-Id: I25e8aba50f509fd74c27cb9cc25b2f4515388f0d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1514280
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Bill Orr <billorr@chromium.org>
Commit-Queue: Takashi Sakamoto <tasak@google.com>
Cr-Commit-Position: refs/heads/master@{#639429}
1 file changed