For lack of a better approach we now initiate the plugin src url download in ...

webkit/glue/webplugin_impl.cc

Index: webkit/glue/webplugin_impl.cc
===================================================================
--- webkit/glue/webplugin_impl.cc	(revision 17977)
+++ webkit/glue/webplugin_impl.cc	(working copy)
@@ -378,7 +378,8 @@
       plugin_url_(plugin_url),
       load_manually_(load_manually),
       first_geometry_update_(true),
-      mime_type_(mime_type) {
+      mime_type_(mime_type),
+      ALLOW_THIS_IN_INITIALIZER_LIST(method_factory_(this)) {
 
   ArrayToVector(arg_count, arg_names, &arg_names_);
   ArrayToVector(arg_count, arg_values, &arg_values_);
@@ -733,13 +734,25 @@
     first_geometry_update_ = false;
     // An empty url corresponds to an EMBED tag with no src attribute.
     if (!load_manually_ && plugin_url_.is_valid()) {
-      HandleURLRequestInternal("GET", false, NULL, 0, NULL, false, false,
-                               plugin_url_.spec().c_str(), NULL, false,
-                               false);
+      // The Flash plugin hangs for a while if it receives data before
+      // receiving valid plugin geometry. By valid geometry we mean the
+      // geometry received by a call to setFrameRect in the Webkit
+      // layout code path. To workaround this issue we download the
+      // plugin source url on a timer.
+      MessageLoop::current()->PostDelayedTask(FROM_HERE,
+          method_factory_.NewRunnableMethod(
+              &WebPluginImpl::OnDownloadPluginSrcUrl),
+          0);
     }
   }
 }
 
+void WebPluginImpl::OnDownloadPluginSrcUrl() {
+  HandleURLRequestInternal("GET", false, NULL, 0, NULL, false, false,
+                           plugin_url_.spec().c_str(), NULL, false,
+                           false);
+}
+
 void WebPluginImpl::paint(WebCore::GraphicsContext* gc,
                           const WebCore::IntRect& damage_rect) {
   if (gc->paintingDisabled())