Specify ordering filediffs by destFilename (Bug 1248008) r?smacleod Backbone's set function performs a merge of the existing models, rather than fully replacing them (New items are added, missing items are removed, and existing items are merged). It appears this merge operation does not preserve the order of the models which are passed into set (instead the existing items end up before the others). Setting the comparator to destFilename tells the set function to sort by that attribute. MozReview-Commit-ID: 5nNeQQ32Sr4

--- a/reviewboard/reviewboard/static/rb/js/diffviewer/collections/diffFileCollection_mozreview.js
+++ b/reviewboard/reviewboard/static/rb/js/diffviewer/collections/diffFileCollection_mozreview.js
@@ -1,6 +1,7 @@
 /*
  * A collection of files.
  */
 RB.DiffFileCollection = Backbone.Collection.extend({
-    model: RB.DiffFile
+    model: RB.DiffFile,
+    comparator: 'destFilename'
 });