extensions: don't animate options dialog when loading.

chrome/browser/resources/extensions/extension_options_overlay.js

Index: chrome/browser/resources/extensions/extension_options_overlay.js
diff --git a/chrome/browser/resources/extensions/extension_options_overlay.js b/chrome/browser/resources/extensions/extension_options_overlay.js
index dc1fbeb832c513c9865cbdb6e8e34fa54b0c15be..e51e8c09e7b675411d5e6bac4b039f93bed4d9b1 100644
--- a/chrome/browser/resources/extensions/extension_options_overlay.js
+++ b/chrome/browser/resources/extensions/extension_options_overlay.js
@@ -131,9 +131,10 @@ cr.define('extensions', function() {
         // the overlay. It is calculated by multiplying the pythagorean distance
         // between old and the new size (in px) with a constant speed of
         // 0.25 ms/px.
-        var animationTime = 0.25 * Math.sqrt(
-            Math.pow(newWidth - oldWidth, 2) +
-            Math.pow(newHeight - oldHeight, 2));
+        var loading = document.documentElement.classlist.contains('loading');
+        var animationTime = loading ? 0 :
+            0.25 * Math.sqrt(Math.pow(newWidth - oldWidth, 2) +
+                             Math.pow(newHeight - oldHeight, 2));
 
         if (animation)
           animation.cancel();