Merge 146016 - Fix a renderer crash when dragging quickly over tab contents.

content/browser/web_contents/web_drag_dest_gtk.cc

Index: content/browser/web_contents/web_drag_dest_gtk.cc
===================================================================
--- content/browser/web_contents/web_drag_dest_gtk.cc	(revision 147031)
+++ content/browser/web_contents/web_drag_dest_gtk.cc	(working copy)
@@ -91,7 +91,6 @@
 
 void WebDragDestGtk::DragLeave() {
   GetRenderViewHost()->DragTargetDragLeave();
-
   if (delegate())
     delegate()->OnDragLeave();
 
@@ -270,6 +269,12 @@
   // as an enter.
   context_ = NULL;
 
+  // Sometimes we get a drag-leave event before getting a drag-data-received
+  // event. In that case, we don't want to bother the renderer with a
+  // DragLeave event.
+  if (data_requests_ != 0)
+    return;
+
   // When GTK sends us a drag-drop signal, it is shortly (and synchronously)
   // preceded by a drag-leave. The renderer doesn't like getting the signals
   // in this order so delay telling it about the drag-leave till we are sure