[GENERIC viewer] Add fallback logic for the old PDFPageView.update method signature

This is done separately from the previous commit, to make it easier to revert these changes in the future.

Author: Snuffleupagus

web/pdf_page_view.js

@@ -298,6 +298,23 @@ class PDFPageView {
   }
 
   update({ scale = 0, rotation = null, optionalContentConfigPromise = null }) {
+    if (
+      typeof PDFJSDev !== "undefined" &&
+      PDFJSDev.test("GENERIC") &&
+      typeof arguments[0] !== "object"
+    ) {
+      console.error(
+        "PDFPageView.update called with separate parameters, please use an object instead."
+      );
+
+      this.update({
+        scale: arguments[0],
+        rotation: arguments[1],
+        optionalContentConfigPromise: arguments[2],
+      });
+      return;
+    }
+
     this.scale = scale || this.scale;
     if (typeof rotation === "number") {
       this.rotation = rotation; // The rotation may be zero.