Adding unit tests for PrerenderDispatcher.

chrome/renderer/prerender/prerender_dispatcher.h

Index: chrome/renderer/prerender/prerender_dispatcher.h
diff --git a/chrome/renderer/prerender/prerender_dispatcher.h b/chrome/renderer/prerender/prerender_dispatcher.h
index 5537401112cb13637d6849b91f2c780a153c335d..45ec51cf7e46b2cc42bbb16e33726953d6a2d61e 100644
--- a/chrome/renderer/prerender/prerender_dispatcher.h
+++ b/chrome/renderer/prerender/prerender_dispatcher.h
@@ -9,6 +9,7 @@
 #include <map>
 
 #include "base/compiler_specific.h"
+#include "base/gtest_prod_util.h"
 #include "content/public/renderer/render_process_observer.h"
 
 class GURL;
@@ -26,6 +27,15 @@ class PrerenderDispatcher : public content::RenderProcessObserver {
   bool IsPrerenderURL(const GURL & url) const;
 
  private:
+  FRIEND_TEST_ALL_PREFIXES(PrerenderDispatcherTest, PrerenderDispatcherEmpty);
+  FRIEND_TEST_ALL_PREFIXES(PrerenderDispatcherTest,
+                           PrerenderDispatcherSingleAdd);
+  FRIEND_TEST_ALL_PREFIXES(PrerenderDispatcherTest,
+                           PrerenderDispatcherMultipleAdd);
+  FRIEND_TEST_ALL_PREFIXES(PrerenderDispatcherTest,
+                           PrerenderDispatcherSingleRemove);
+  FRIEND_TEST_ALL_PREFIXES(PrerenderDispatcherTest,
+                           PrerenderDispatcherMultipleRemove);
   void OnAddPrerenderURL(const GURL& url);
   void OnRemovePrerenderURL(const GURL& url);