Invoke JS messaging for UIWebView via window.requestAnimationFrame

ios/web/web_state/js/resources/message_dynamic_ui.js

Index: ios/web/web_state/js/resources/message_dynamic_ui.js
diff --git a/ios/web/web_state/js/resources/message_dynamic_ui.js b/ios/web/web_state/js/resources/message_dynamic_ui.js
index d3118141228e161eaf01fabbea36d46c55866598..323b21dc7ca21ed9ddbd45ed82d1a0a71819a93e 100644
--- a/ios/web/web_state/js/resources/message_dynamic_ui.js
+++ b/ios/web/web_state/js/resources/message_dynamic_ui.js
@@ -16,27 +16,47 @@ __gCrWeb.message_dynamic = {};
 /* Beginning of anonymous object. */
 new function() {
   /**
+   * Returns true if sending the message queue should be delayed.
+   */
+  function pageRequiresDelayedSend() {
+    // The Apple mobile password recovery page does not interact well with
+    // iframes, so on pages with the 'iforgot.apple.com' domain, delay sending
+    // the queue.
+    return window.location.origin === "https://iforgot.apple.com";
+  }
+
+  /**
    * Sends queued commands to the Objective-C side.
    * @param {Object} queueObject Queue object containing messages to send.
    */
   __gCrWeb.message_dynamic.sendQueue = function(queueObject) {
-    // The technique requires the document to be present. If it is not, the
-    // messages will be sent once the document object is created.
-    if (!document || !document.body) {
-      // This happens in rare occasions early in the page cycle. It is
-      // possible to create a body element indirectly here, but it has side
-      // effects such as blocking page redirection. The safest solution is to
-      // try again in 1/10th of a second.
-      window.setTimeout(__gCrWeb.message.invokeQueues, 100);
-      return;
-    }
+    var send = function() {
+      // The technique requires the document to be present. If it is not, the
+      // messages will be sent once the document object is created.
+      if (!document || !document.body) {
+        // This happens in rare occasions early in the page cycle. It is
+        // possible to create a body element indirectly here, but it has side
+        // effects such as blocking page redirection. The safest solution is to
+        // try again in 1/10th of a second.
+        window.setTimeout(__gCrWeb.message.invokeQueues, 100);
+        return;
+      }
+
+      var frame = document.createElement('iframe');
+      frame.style.display = 'none';
+      frame.src = queueObject.scheme + '://' + __gCrWeb.windowId + '#' +
+          encodeURIComponent(__gCrWeb.common.JSONStringify(queueObject.queue));
+      queueObject.reset();
+      document.body.appendChild(frame);
+      document.body.removeChild(frame);
+    };
 
-    var frame = document.createElement('iframe');
-    frame.style.display = 'none';
-    frame.src = queueObject.scheme + '://' + __gCrWeb.windowId + '#' +
-        encodeURIComponent(__gCrWeb.common.JSONStringify(queueObject.queue));
-    queueObject.reset();
-    document.body.appendChild(frame);
-    document.body.removeChild(frame);
+    // Some pages do not interact well with iframes. On those pages, delay
+    // sending the queue.
+    if (pageRequiresDelayedSend()) {
+      window.requestAnimationFrame(send);
+    } else {
+      send();
+    }
   };
 }