Update window title when a pane item's title changes

src/app/pane.coffee

@@ -94,10 +94,13 @@ class Pane extends View
   showItem: (item) ->
     return if !item? or item is @activeItem
 
-    @autosaveActiveItem() if @activeItem
+    if @activeItem
+      @activeItem.off? 'title-changed', @activeItemTitleChanged
+      @autosaveActiveItem()
 
     isFocused = @is(':has(:focus)')
     @addItem(item)
+    item.on? 'title-changed', @activeItemTitleChanged
     view = @viewForItem(item)
     @itemViews.children().not(view).hide()
     @itemViews.append(view) unless view.parent().is(@itemViews)
@@ -107,6 +110,9 @@ class Pane extends View
     @activeView = view
     @trigger 'pane:active-item-changed', [item]
 
+  activeItemTitleChanged: =>
+    @trigger 'pane:active-item-title-changed'
+
   addItem: (item) ->
     return if _.include(@items, item)
     index = @getActiveItemIndex() + 1

src/app/root-view.coffee

@@ -32,8 +32,6 @@ class RootView extends View
     panes = deserialize(panesViewState) if panesViewState?.deserializer is 'PaneContainer'
     new RootView({panes})
 
-  title: null
-
   initialize: ->
     @command 'toggle-dev-tools', => atom.toggleDevTools()
     @on 'focus', (e) => @handleFocus(e)
@@ -44,6 +42,7 @@ class RootView extends View
     @on 'pane:became-active', => @updateTitle()
     @on 'pane:active-item-changed', '.active.pane', => @updateTitle()
     @on 'pane:removed', => @updateTitle() unless @getActivePane()
+    @on 'pane:active-item-title-changed', '.active.pane', => @updateTitle()
 
     @command 'window:increase-font-size', =>
       config.set("editor.fontSize", config.get("editor.fontSize") + 1)