Handle interface to prerenders.

chrome/browser/prerender/prerender_handle.h

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_PRERENDER_PRERENDER_HANDLE_H_
+#define CHROME_BROWSER_PRERENDER_PRERENDER_HANDLE_H_
+
+#include "base/threading/non_thread_safe.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
+
+class GURL;
+
+namespace content {
+class SessionStorageNamespace;
+}
+
+namespace prerender {
+
+class PrerenderContents;
+class PrerenderManager;
+
+class PrerenderHandleImpl : public base::SupportsWeakPtr<PrerenderHandleImpl>,
+                            public base::NonThreadSafe {
+ public:
+  ~PrerenderHandleImpl();
+
+  bool IsPending() const;
+  bool IsPrerendering() const { return !IsPending(); }
+
+  bool DidFinishLoading() const;
+
+  void Release();
+
+ protected:
+  friend class PrerenderBrowserTest;
+  friend class PrerenderContents;
+  friend class PrerenderManager;
+
+  PrerenderHandleImpl();
+
+  void AddDuplicate(PrerenderHandleImpl* new_duplicate_handle);
+  void AddClient();
+
+  PrerenderContents* contents() const { return contents_; }
+  void SetContents(PrerenderContents* contents);
+
+ private:
+  PrerenderContents* contents_;
+
+  // Another prerender handle, owned by this one, which refers to the same
+  // PrerenderContents. This ends up being effectively a list, since our

[dominich, 2012/06/28 00:34:32]

my non-lisp brain still wants this to be a scoped_vector<PrerenderHandleImpl>
instances_; or something similar.

+  // duplicate_handle_ can itself have a duplicate_handle_.
+  scoped_ptr<PrerenderHandleImpl> duplicate_handle_;
+};

[mmenke, 2012/06/28 16:01:28]

How not get rid of duplicate_handle_ and AddDuplicate?  Just call AddClient and
return the original handle.  I don't see why you need more than one of them,
they don't have any individual state, and you aren't doing anything in their
destructors (And can't, for that matter).

[mmenke, 2012/06/28 16:02:32]

Erm...  That should be "Why not just get" (Or "How about getting", take your
pick).

+
+typedef base::WeakPtr<PrerenderHandleImpl> PrerenderHandle;

[dominich, 2012/06/28 00:34:32]

i love this so hard.

+
+}  // namespace prerender
+
+#endif  // CHROME_BROWSER_PRERENDER_PRERENDER_HANDLE_H_