Fix ChromeFrame test failures on IE8 which occurred because we did not handle the case

where a new AutomationResourceMessageFilter instance was created for a render view/render process id
combination. This happens typically on IE8 and above where new windows could go into a different IE process.

BUG=none
TBR=robertshield
Review URL: http://codereview.chromium.org/8414038

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@107827 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/automation/automation_resource_message_filter.cc

@@ -262,7 +262,11 @@ void AutomationResourceMessageFilter::RegisterRenderViewInIOThread(
 
   RenderViewMap::iterator automation_details_iter(
       filtered_render_views_.Get().find(renderer_key));
-  if (automation_details_iter != filtered_render_views_.Get().end()) {
+  // We need to match the renderer key and the AutomationResourceMessageFilter
+  // instances. If the filter instances are different it means that a new
+  // automation channel (External host process) was created for this tab.
+  if (automation_details_iter != filtered_render_views_.Get().end() &&
+      automation_details_iter->second.filter == filter) {
     DCHECK_GT(automation_details_iter->second.ref_count, 0);
     automation_details_iter->second.ref_count++;
     // The tab handle may have changed:-