Issue 3258 - Blockable items: fix Size column

lib/child/requestNotifier.js

Index: lib/child/requestNotifier.js
===================================================================
--- a/lib/child/requestNotifier.js
+++ b/lib/child/requestNotifier.js
@@ -31,21 +31,23 @@ let requestEntryMaxId = 0;
  * Active RequestNotifier instances by their ID
  * @type Map.<number,RequestNotifier>
  */
 let notifiers = new Map();
 
 addMessageListener("AdblockPlus:StartWindowScan", onStartScan);
 addMessageListener("AdblockPlus:ShutdownNotifier", onNotifierShutdown);
 addMessageListener("AdblockPlus:FlashNodes", onFlashNodes);
+addMessageListener("AdblockPlus:RetrieveNodeSize", onRetrieveNodeSize);
 
 onShutdown.add(() => {
   removeMessageListener("AdblockPlus:StartWindowScan", onStartScan);
   removeMessageListener("AdblockPlus:ShutdownNotifier", onNotifierShutdown);
   removeMessageListener("AdblockPlus:FlashNodes", onFlashNodes);
+  removeMessageListener("AdblockPlus:RetrieveNodeSize", onRetrieveNodeSize);
 });
 
 function onStartScan(message)
 {
   let {notifierID, outerWindowID} = message.data;
   let window = Services.wm.getOuterWindowWithId(outerWindowID);
   if (window)
     new RequestNotifier(window, notifierID);
@@ -61,16 +63,24 @@ function onNotifierShutdown(message)
 function onFlashNodes(message)
 {
   let {notifierID, requests, scrollToItem} = message.data;
   let notifier = notifiers.get(notifierID);
   if (notifier)
     notifier.flashNodes(requests, scrollToItem);
 }
 
+function onRetrieveNodeSize(message)
+{
+  let {notifierID, responseID, requests} = message.data;
+  let notifier = notifiers.get(notifierID);
+  if (notifier)
+    notifier.retrieveNodeSize(requests, responseID);
+}
+
 /**
  * Creates a notifier object for a particular window. After creation the window
  * will first be scanned for previously saved requests. Once that scan is
  * complete only new requests for this window will be reported.
  * @param {Window} window  window to attach the notifier to
  * @param {Integer} notifierID  Parent notifier ID to be messaged
  */
 function RequestNotifier(window, notifierID)
@@ -213,16 +223,58 @@ RequestNotifier.prototype =
   /**
    * Stops flashing nodes after a previous flashNodes() call.
    */
   stopFlashing: function()
   {
     if (this.flasher)
       this.flasher.stop();
     this.flasher = null;
+  },
+
+  /**
+   * Attempts to calculate the size of the nodes associated with the requests,
+   * Sends message to parent when complete.
+   * @param {number[]} requests  list of request IDs that were previously
+   *                             reported by this notifier.
+   * @param {number} responseID  ID to be sent with the response.
+   */
+  retrieveNodeSize: function(requests, responseID)
+  {
+    function getNodeSize(node)
+    {
+      if (node instanceof Ci.nsIDOMHTMLImageElement && (node.naturalWidth || node.naturalHeight))
+        return [node.naturalWidth, node.naturalHeight];
+      else if (node instanceof Ci.nsIDOMHTMLElement && (node.offsetWidth || node.offsetHeight))
+        return [node.offsetWidth, node.offsetHeight];
+      else
+        return null;
+    }
+
+    let size = null;
+    for (let id of requests)
+    {
+      if (!this.nodes.has(id))
+        continue;
+
+      let node = this.nodes.get(id);
+      if (Cu.isDeadWrapper(node))
+        this.nodes.delete(node);
+      else
+      {
+        size = getNodeSize(node);
+        if (size)
+          break;
+      }
+    }
+    sendAsyncMessage("AdblockPlus:RetrieveNodeSizeResponse", {
+      notifierID: this.id,
+      responseID,
+      size
+    });
   }
 };
 
 /**
  * Attaches request data to a DOM node.
  * @param {Node} node   node to attach data to
  * @param {Window} topWnd   top-level window the node belongs to
  * @param {Object} hitData