Merge pull request #8285 from davidflanagan/bug833300

Bug 833300 - make input field clear buttons work in email app r=asuth(cherry picked from commit ac50d89ea2ece880337b4e085d80e570359086e0)
Merge pull request #8319 from jmcanterafonseca/fix_link

[Bug 841716] [CONTACTS][FACEBOOK] Link contact to a facebook contact is ...(cherry picked from commit cb8953c8a686816f85f60144b991e7245d219bb2)
Bug 843204 - Add UA overrides requested by Everything.me
(cherry picked from commit e4fb12ad7a5162327162c9592677f1fb0a327b51)