Backed out changeset 6debf3390ba2 (bug 1646609) for mochitest failures on docshell/base/BrowsingContext.cpp

commitde6876fd1fecdc0640613f2adefdfa69a462a916
parent347cd24124505ba0edc8c33ca859334a97ebcf79
hge950bdd669d44eeb8e6af84a987c2a8ba5d9d1a2
gitde6876fd1fecdc0640613f2adefdfa69a462a916
old mozilla-central git revs:31d8600b73dc85b4cdbabf45ac3f1a9c11700d8e
authorCoroiu Cristina <ccoroiu@mozilla.com>
committerCoroiu Cristina <ccoroiu@mozilla.com>
commit timeWed, 1 Jul 2020 08:39:53 +0300