Fix bug #7112 (Out-of-scope files added to Find in Files results) - apply
all the same filtering when updating incrementally as we do when performing
the initial search.

Consolidate many of these checks in a new _inSearchScope() and rename the
old _inScope() to sound less confusingly similar.

Also: tweak Dialog to allow closing with Ctrl+Enter when focus is in a
textarea (where regular Enter is prevented from closing). Helps filter
editing.
Clean up event listener adding/removing in FindInFiles code so listeners
are consistently added exactly 1 time while results are visible:
- Supercedes original fix for #6923 (PR #7106) - FileSystem listener re-added
each time results updated or paged.
- Fixes issue where Document listener added even when 0 results, in which
case panel isn't shown (it used to excplicitly check for this case in order
to ignore changes).
- Fixes issue where Document listener re-added each time a new search is
run without closing the old results first.
Merge remote-tracking branch 'origin/master' into pflynn/respect-find-filter

* origin/master:
  JSLint whitespace fix
  Fix edge case for #7075 where selection ends at beginning of last line of document
  Adds deprecation warnings for setAllValues and Remove
  Fix bug #6923 (Brackets freezes for a while after saving when Find in Files panel is open) - Ensure we're not accumulating many copies of the FileSystem "change" listener.
  Update ScrollTrackMarkers positioning metrics to better match the scrollbar on each platform - especially Windows, which changed greatly last sprint when we switched to custom scrollbar styling (causing #7058, noticeably innaccurate tickmark positioning).
  Simplify the code to fix the issue of unable to delete falsy preference values that I introduced. Add one more unit test for removing falsy preference values and explicit checks for dirty flags in the previous two unit tests.
  Add two unit tests to verify that we're not updating the preferences if the value is the same.
  Don't set dirty flag for layer preferences also if not updating. Also return false if we don't really update.
  For #7075, don't delete the last line if the selection ends right at the beginning
  Don't set dirty flag if the preference value does not change so that we don't write out to the preferences file.

Conflicts:
	src/search/FindInFiles.js
Code review: add docs, tweak whitespace lines
Merge pull request #7115 from adobe/pflynn/respect-find-filter

Fix bug #7112 (Out-of-scope files added to Find in Files results)