RootView.open takes an 'allowActiveEditorChange' option

When the 'allowActiveEditorChange' option is true, RootView will try to activate an existing edit session for the given path on *any* editor, and switch focus there. This will be used by the fuzzy-finder for the meta-b option, which should open the chosen buffer on the editor that contains it, even if it isn't currently active.

src/app/editor.coffee

@@ -389,6 +389,13 @@ class Editor extends View
 
     @renderWhenAttached()
 
+  activateEditSessionForPath: (path) ->
+    for editSession, index in @editSessions
+      if editSession.buffer.getPath() == path
+        @setActiveEditSessionIndex(index)
+        return true
+    false
+
   getOpenBufferPaths: ->
     editSession.buffer.path for editSession in @editSessions when editSession.buffer.path?