Adding MimeHandlerView.

content/renderer/render_frame_impl.cc

Index: content/renderer/render_frame_impl.cc
diff --git a/content/renderer/render_frame_impl.cc b/content/renderer/render_frame_impl.cc
index af2987fda5b30c540abe6ed6ac8ce081e87930e2..61a6221eed05585dd4cc43cbcf08889cc6c145da 100644
--- a/content/renderer/render_frame_impl.cc
+++ b/content/renderer/render_frame_impl.cc
@@ -1338,8 +1338,9 @@ blink::WebPlugin* RenderFrameImpl::createPlugin(
     const blink::WebPluginParams& params) {
   DCHECK_EQ(frame_, frame);
   blink::WebPlugin* plugin = NULL;
+  int instance_id;
   if (GetContentClient()->renderer()->OverrideCreatePlugin(
-          this, frame, params, &plugin)) {
+          this, frame, params, &instance_id, &plugin)) {
     return plugin;
   }
 
@@ -1359,8 +1360,11 @@ blink::WebPlugin* RenderFrameImpl::createPlugin(
     return NULL;
 
   if (info.type == content::WebPluginInfo::PLUGIN_TYPE_BROWSER_PLUGIN) {
-    return render_view_->GetBrowserPluginManager()->CreateBrowserPlugin(
-        render_view_.get(), frame, true);
+    BrowserPlugin* plugin =
+        render_view_->GetBrowserPluginManager()->CreateBrowserPlugin(
+            render_view_.get(), frame, true);
+    plugin->AttachToPlugin(instance_id);
+    return plugin;
   }