Prevented connecting drag drop events to a SwappedOut RenderViewHost in WebContentsViewGtk

content/browser/web_contents/web_contents_view_gtk.cc

Index: content/browser/web_contents/web_contents_view_gtk.cc
diff --git a/content/browser/web_contents/web_contents_view_gtk.cc b/content/browser/web_contents/web_contents_view_gtk.cc
index 8f64ef04175b463e027559e10f41676c08bc9757..9c091b875d5aed5e91b68f437d79bdb806ed8214 100644
--- a/content/browser/web_contents/web_contents_view_gtk.cc
+++ b/content/browser/web_contents/web_contents_view_gtk.cc
@@ -128,6 +128,15 @@ RenderWidgetHostView* WebContentsViewGtk::CreateViewForWidget(
   RenderWidgetHostView* view =
       RenderWidgetHostView::CreateViewForWidget(render_widget_host);
   view->InitAsChild(NULL);
+  if (render_widget_host->IsRenderView()) {
+    RenderViewHost* rvh = RenderViewHost::From(render_widget_host);
+    // A swapped out RenderViewHost is not visible, and so there is no reason
+    // to connect events to it, or use it as a WebDragDest (It won't be able
+    // to receive drag updates, and may break drag and drop in a window).
+    if (web_contents_->GetRenderManagerForTesting()->IsSwappedOut(rvh)) {

[Fady Samuel, 2013/02/13 21:15:22]

This looks wrong...GetRenderManagerForTesting is supposed to be used in testing
only (hence the name).

However, I don't necessarily have a better solution. I'll let Evan guide you on
this one. 

[Charlie Reis, 2013/02/20 06:42:45]

Fady's right-- this would be a layering violation.  RenderViewHostManager is not
supposed to be exposed outside WebContentsImpl.

An alternative is to use RenderViewHostImpl::is_swapped_out(), but I think
that's just masking the underlying problem.  This method shouldn't be called
with a swapped out RVH in the first place.

In most cases, we filter out the messages sent to/from a swapped out RVH (see
swapped_out_messages.cc).  Is there a comparable place we could be preventing
this bug at an earlier stage?

+      return view;
+    }
+  }
   gfx::NativeView content_view = view->GetNativeView();
   g_signal_connect(content_view, "focus", G_CALLBACK(OnFocusThunk), this);
   g_signal_connect(content_view, "leave-notify-event",