Use Subscriber::subscribe for telepath change listeners

src/display-buffer.coffee

@@ -50,7 +50,7 @@ class DisplayBuffer
     @subscribe @buffer, 'markers-updated', @handleBufferMarkersUpdated
     @subscribe @buffer, 'marker-created', @handleBufferMarkerCreated
 
-    @state.on 'changed', ({key, newValue}) =>
+    @subscribe @state, 'changed', ({key, newValue}) =>
       switch key
         when 'softWrap'
           @trigger 'soft-wrap-changed', newValue

src/edit-session.coffee

@@ -73,7 +73,7 @@ class EditSession
       @addCursorAtBufferPosition(position)
 
     @languageMode = new LanguageMode(this, @buffer.getExtension())
-    @state.on 'changed', ({key, newValue}) =>
+    @subscribe @state, 'changed', ({key, newValue}) =>
       switch key
         when 'scrollTop'
           @trigger 'scroll-top-changed', newValue

src/pane-container.coffee

@@ -25,7 +25,7 @@ class PaneContainer extends View
     else
       @state = site.createDocument(deserializer: 'PaneContainer')
 
-    @state.on 'changed', ({key, newValue, site}) =>
+    @subscribe @state, 'changed', ({key, newValue, site}) =>
       return if site is @state.site.id
       if key is 'root'
         if newValue?

src/pane.coffee

@@ -36,14 +36,14 @@ class Pane extends View
         deserializer: 'Pane'
         items: @items.map (item) -> item.getState?() ? item.serialize()
 
-    @state.get('items').on 'changed', ({index, removed, inserted, site}) =>
+    @subscribe @state.get('items'), 'changed', ({index, removed, inserted, site}) =>
       return if site is @state.site.id
       for itemState in removed
         @removeItemAtIndex(index, updateState: false)
       for itemState, i in inserted
         @addItem(deserialize(itemState), index + i, updateState: false)
 
-    @state.on 'changed', ({key, newValue, site}) =>
+    @subscribe @state, 'changed', ({key, newValue, site}) =>
       return if site is @state.site.id
       @showItemForUri(newValue) if key is 'activeItemUri'