Add two small features to the HttpCache for benchmarking/debugging....

net/http/http_cache.h

Index: net/http/http_cache.h
===================================================================
--- net/http/http_cache.h	(revision 17638)
+++ net/http/http_cache.h	(working copy)
@@ -48,7 +48,10 @@
     RECORD,
     // Playback mode replays from a cache without considering any
     // standard invalidations.
-    PLAYBACK
+    PLAYBACK,
+    // Disables reads and writes from the cache.
+    // Equivalent to setting LOAD_DISABLE_CACHE on every request.
+    DISABLE
   };
 
   // Initialize the cache from the directory where its data is stored. The
@@ -103,6 +106,9 @@
   void set_type(CacheType type) { type_ = type; }
   CacheType type() { return type_; }
 
+  // Close All Idle Sockets.  This is for debugging.
+  void CloseIdleConnections();
+
  private:
 
   // Types --------------------------------------------------------------------