Initial implementation of Quick Edit grouping the results list by file, in
collapsible sections.

Also, remove async code from _updateSelectedMarker() (seems to be a very
old remnant from when we allowed scrolling in the rule list, which we don't
anymore) and stop returning a Promise (no one was using it anyway).
Quick Edit grouping fixes:
- properly persist collapsed sections preference (explicit layerID required)
- adjust inline widget height when sections collapsed/expanded
- fix bug where collapsed sections popped back open after add/remove rule
- show message when all results are in collapsed sections

Plus some cleanups:
- document messageCB & labelCB better
- remove unneeded fixed height on $relatedContainer
- cleanup unused args to sizeInlineWidgetToContents()
Updated by ALF automation.
Merge branch 'master' into alf_localization
Merge branch 'master' into alf_localization
Merge branch 'master' into alf_localization
Merge branch 'master' into alf_localization
Updated by ALF automation.
Merge branch 'master' into alf_localization
Updated by ALF automation.
Merge branch 'master' into alf_localization
Spanish translation for release 0.44 and other fixes
sprint 44 - czech language

updated
Merge branch 'master' into alf_localization
Update strings.js
Fix bug #9451 (Dark Theme: active line w/o line numbers has wrong color in
gutter) -- .show-line-padding is now on the Pane rather than #editor-holder
Merge branch 'master' into alf_localization
Merge branch 'master' into alf_localization
Implement custom keyboard shortcuts support with a user key map file.
Merge remote-tracking branch 'origin' into rlim/custom-key-map