Reset scroll margins when changing document

services/web/public/coffee/ide/editor/directives/aceEditor.coffee

@@ -187,20 +187,25 @@ define [
 				scope.$on "#{scope.name}:set-scroll-size", (e, size) ->
 					# Make sure that the editor has enough scroll margin above and below
 					# to scroll the review panel with the given size
-					marginChanged = false
-					if editor.renderer.scrollMargin.top != size.overflowTop
-						window.editors[0].renderer.scrollMargin.top = size.overflowTop
-						marginChanged = true
-
+					marginTop = size.overflowTop
 					maxHeight = editor.renderer.layerConfig.maxHeight
 					marginBottom = Math.max(size.height - maxHeight, 0)
+					setScrollMargins(marginTop, marginBottom)
+
+				setScrollMargins = (marginTop, marginBottom) ->
+					marginChanged = false
+					if editor.renderer.scrollMargin.top != marginTop
+						editor.renderer.scrollMargin.top = marginTop
+						marginChanged = true
 					if editor.renderer.scrollMargin.bottom != marginBottom
 						editor.renderer.scrollMargin.bottom = marginBottom
 						marginChanged = true
-
 					if marginChanged
 						editor.renderer.updateFull()
 
+				resetScrollMargins = () ->
+					setScrollMargins(0,0)
+
 				scope.$watch "theme", (value) ->
 					editor.setTheme("ace/theme/#{value}")
 
@@ -325,6 +330,8 @@ define [
 					sharejs_doc.attachToAce(editor)
 					editor.initing = false
 
+					resetScrollMargins()
+
 					# need to set annotations after attaching because attaching
 					# deletes and then inserts document content
 					session.setAnnotations scope.annotations