First pass at adding http/backend cache to NetLog

net/disk_cache/backend_impl.h

Index: net/disk_cache/backend_impl.h
===================================================================
--- net/disk_cache/backend_impl.h	(revision 70512)
+++ net/disk_cache/backend_impl.h	(working copy)
@@ -19,6 +19,10 @@
 #include "net/disk_cache/stats.h"
 #include "net/disk_cache/trace.h"
 
+namespace net {
+class NetLog;
+}  // namespace net
+
 namespace disk_cache {
 
 enum BackendFlags {
@@ -38,10 +42,11 @@
 class BackendImpl : public Backend {
   friend class Eviction;
  public:
-  BackendImpl(const FilePath& path, base::MessageLoopProxy* cache_thread);
+  BackendImpl(const FilePath& path, base::MessageLoopProxy* cache_thread,
+              net::NetLog* net_log);
   // mask can be used to limit the usable size of the hash table, for testing.
   BackendImpl(const FilePath& path, uint32 mask,
-              base::MessageLoopProxy* cache_thread);
+              base::MessageLoopProxy* cache_thread, net::NetLog* net_log);
   ~BackendImpl();
 
   // Returns a new backend with the desired flags. See the declaration of
@@ -49,7 +54,8 @@
   static int CreateBackend(const FilePath& full_path, bool force,
                            int max_bytes, net::CacheType type,
                            uint32 flags, base::MessageLoopProxy* thread,
-                           Backend** backend, CompletionCallback* callback);
+                           net::NetLog* net_log, Backend** backend,
+                           CompletionCallback* callback);
 
   // Performs general initialization for this current instance of the cache.
   int Init(CompletionCallback* callback);
@@ -357,6 +363,8 @@
   bool first_timer_;  // True if the timer has not been called.
   bool throttle_requests_;
 
+  net::NetLog* net_log_;
+
   Stats stats_;  // Usage statistcs.
   base::RepeatingTimer<BackendImpl> timer_;  // Usage timer.
   base::WaitableEvent done_;  // Signals the end of background work.