
If the user views a very large diff while "Whole file" is enabled in their preferences, rendering may lock up their browser. With this change, instead of rendering, users are warned and allowed to bypass the warning (risking browser lock up) or render with a context that is less than whole file. Bug: Issue 6402 Change-Id: I6e97c06598fb5f6900c925127ab6a99693b8aa7f