Merge revision 736 and revision 737 changes:

- Fix crashes/assertions when CefBrowserImpl is destroyed on a non-UI thread (issue #694).
- Improve the handling of invalidation/painting for off-screen rendering (issue #695).

git-svn-id: https://chromiumembedded.googlecode.com/svn/branches/1025@738 5089003a-bbd8-11dd-ad1f-f1f9622dbc98

libcef/dom_node_impl.cc

@@ -11,6 +11,7 @@
 
 #include "base/logging.h"
 #include "base/string_util.h"
+#include "base/threading/non_thread_safe.h"
 #include "base/utf_string_conversions.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebAttribute.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebDocument.h"
@@ -42,7 +43,8 @@ namespace {
 
 // Wrapper implementation for WebDOMEventListener.
 class CefDOMEventListenerWrapper : public WebDOMEventListener,
-                                   public CefTrackNode {
+                                   public CefTrackNode,
+                                   public base::NonThreadSafe {
  public:
   CefDOMEventListenerWrapper(CefBrowserImpl* browser, WebFrame* frame,
                              CefRefPtr<CefDOMEventListener> listener)
@@ -53,7 +55,6 @@ class CefDOMEventListenerWrapper : public WebDOMEventListener,
     browser->UIT_AddFrameObject(frame, this);
   }
   virtual ~CefDOMEventListenerWrapper() {
-    REQUIRE_UIT();
   }
 
   virtual void handleEvent(const WebDOMEvent& event) {