Merge pull request #14831 from mpizza/Bug_937487_handle_activity

Bug 937487 - Keyboard won't disappear after focusing an input and then l... r=alive.
(cherry picked from commit e8dfed06a8524c0d72c0c96c83341562754164fc)
Merge pull request #15285 from mpizza/Bug_937487_v1.3

Merge pull request #14831 from mpizza/Bug_937487_handle_activity