Bug 937336 - Remove where possible explicit frame switching

Changes to Contacts app, where possible
Merge pull request #14103 from mikehenrty/bug-926347-dualsim2

Bug 926347 dualsim2
Bug 951107 - alpha scroll in export contacts screen is broken
Merge pull request #14666 from pivanov/bug-950103

Bug 950103 - [Settings] Update wifi sprite
Merge pull request #14818 from pivanov/bug-951823

Bug 951823 - [BB]Headers - option to use nested and combine skins for Headers and other [BB]
Merge pull request #14750 from jmcanterafonseca/fix_export_alpha_scroll

Bug 951107 - alpha scroll in export contacts screen is broken
Bug 937336 - Remove where possible explicit frame switching

Remove explicit frame switching *and* unneeded locators from videoplayer app
Bug 937336 - Remove where possible explicit frame switching

Replace calls to marionette.switch_to_frame(self.app.frame) in FTU test with apps.switch_to_displayed_app()
Bug 937336 - Remove where possible explicit frame switching

Remove explicit frame switching from keyboard tests
Bug 937336 - Remove where possible explicit frame switching

Change to Persona test
Bug 913326 - Set voice privacy mode at startup
Bug 951985 - Unxfail test_gallery_crop_photo.py and test_browser_play_youtube_video.py
Merge pull request #14256 from huchengtw-moz/gallery/Bug_877521_the_warning_message_of_pick_is_wrong

Bug 877521 - [Contacts][UX] The warning message of add picture is wrong., r=djf
Bug 937487 - Keyboard won't disappear after focusing an input and then launch an activity
Merge pull request #14610 from crdlc/bug-948934

Bug 948934 - [Download Manager] The downloading icon is not displayed du...
Bug 907740 - [messages] sending message to Facebook contacts results in phone number not contact name being displayed
Merge pull request #14777 from gtorodelvalle/contacts-bug-948817-enter-clears-custom-tag

Bug 948817 - [fugu][buri][contact] tap on 'enter' on keyboard will clear all input in custom label (r=jmcanterafonseca)
Bug 949799 - [B2G][Geolocation] 'More Info' icon is unresponsive on the Geolocation screen
Merge pull request #14683 from snowmantw/issue945601

Bug 945601 - [LockScreen] The acceleration mode of LockScreen should be more smooth
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.