[api-minor] Allow specifying an extra-delay, in RenderTask.cancel, for worker-thread aborting of operatorList parsing

This is done to support upcoming viewer-changes, and in order to prevent third-party users from outright breaking things we'll simply ignore too large values.

src/display/display_utils.js

@@ -332,9 +332,10 @@ class PageViewport {
 }
 
 class RenderingCancelledException extends BaseException {
-  constructor(msg, type) {
+  constructor(msg, type, extraDelay = 0) {
     super(msg, "RenderingCancelledException");
     this.type = type;
+    this.extraDelay = extraDelay;
   }
 }