Active line highlight doesn't disappear in unfocused editor

[njx]

1. Turn on View > Highlight Active Line
2. Open an inline editor
3. Click in the inline editor
4. Click back in the main editor

Result: Both editors always show active lines.
Expected: Active line should only show in focused editor.

[TomMalbran]

I think this might need to be changed in the CodeMirror addon, or it would require a hack in Brackets to remove the highlight line class of the active line when the focus changes. An alternative would be to toggle Highlight Active Line it on and off to let the addon remove the classes.

[RaymondLim]

@TomMalbran

I think we can handle it in Brackets by always setting a new "activeEditor" class to the active editor and remove that class when it is no longer active. Then we can add the new "activeEditor" class selector to all the rules that have ".CodeMirror-activeline-background" selector. Then split all the rules with ".CodeMirror-activeline-background" selector to two -- one with the new ".activeEditor"" class selector that has active-line background color and the other with ":not(.activeEditor)" class selector that has normal background color.