Code quality and standards in SimpleBackend.

net/disk_cache/simple/simple_backend_impl.h

Index: net/disk_cache/simple/simple_backend_impl.h
diff --git a/net/disk_cache/simple/simple_backend_impl.h b/net/disk_cache/simple/simple_backend_impl.h
index eab0164521d9ba12497bc4bdcfda030a2d334920..91ce88726eacf38ed1f414c5b4410099ed2c022c 100644
--- a/net/disk_cache/simple/simple_backend_impl.h
+++ b/net/disk_cache/simple/simple_backend_impl.h
@@ -12,10 +12,10 @@
 #include "base/compiler_specific.h"
 #include "base/files/file_path.h"
 #include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
 #include "base/task_runner.h"
 #include "net/base/cache_type.h"
 #include "net/disk_cache/disk_cache.h"
-#include "net/disk_cache/simple/simple_index.h"
 
 namespace base {
 class MessageLoopProxy;
@@ -31,11 +31,13 @@ namespace disk_cache {
 
 // See http://www.chromium.org/developers/design-documents/network-stack/disk-cache/very-simple-backend
 
+class SimpleIndex;
+
 class NET_EXPORT_PRIVATE SimpleBackendImpl : public Backend {
  public:
   SimpleBackendImpl(const base::FilePath& path, int max_bytes,
                     net::CacheType type,
-                    const scoped_refptr<base::TaskRunner>& cache_thread,
+                    base::TaskRunner* cache_thread,

[Philippe, 2013/04/18 09:30:10]

What kind of guarantees do you need from this TaskRunner (and others)? I suspect
that you actually need a SingleThreadTaskRunner. For example, TaskRunner does
not guarantee the order in which posted tasks are run. It's a very high level
abstraction. In practice it will work as expected since you will provide an
instance of the correct implementation but I would suggest better expressing
your expectations here with a SingleThreadTaskRunner.

This would significantly increase the diff though :/

[gavinp, 2013/04/18 09:46:18]

Done.

                     net::NetLog* net_log);
 
   virtual ~SimpleBackendImpl();
@@ -79,7 +81,7 @@ class NET_EXPORT_PRIVATE SimpleBackendImpl : public Backend {
       const InitializeIndexCallback& initialize_index_callback);
 
   const base::FilePath path_;
-  scoped_refptr<SimpleIndex> index_;
+  scoped_ptr<SimpleIndex> index_;
   const scoped_refptr<base::TaskRunner> cache_thread_;
 };