New link rel=prerender api, using WebKit::WebPrerenderingPlatform

chrome/browser/prerender/prerender_link_manager.h

Index: chrome/browser/prerender/prerender_link_manager.h
diff --git a/chrome/browser/prerender/prerender_link_manager.h b/chrome/browser/prerender/prerender_link_manager.h
new file mode 100644
index 0000000000000000000000000000000000000000..04d342965dd44c1c1c318fecc2d9f7a10e015dd1
--- /dev/null
+++ b/chrome/browser/prerender/prerender_link_manager.h
@@ -0,0 +1,94 @@
+// 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_LINK_MANAGER_H_
+#define CHROME_BROWSER_PRERENDER_PRERENDER_LINK_MANAGER_H_
+#pragma once
+
+#include <map>
+#include <utility>
+
+#include "base/basictypes.h"
+#include "base/gtest_prod_util.h"
+#include "chrome/browser/profiles/profile_keyed_service.h"
+#include "googleurl/src/gurl.h"
+
+class Profile;
+
+namespace content {
+struct Referrer;
+}
+
+namespace gfx {
+class Size;
+}
+
+namespace prerender {
+
+class PrerenderManager;
+
+// PrerenderLinkManager implements the API on Link elements for all documents
+// being rendered in this chrome instance.  It receives messages from the
+// renderer indicating addition, cancelation and abandonment of link elements,
+// and controls the PrerenderManager accordingly.
+class PrerenderLinkManager : public ProfileKeyedService {
+ public:
+  explicit PrerenderLinkManager(PrerenderManager* manager);
+  virtual ~PrerenderLinkManager();
+
+  // A <link rel=prerender ...> element has been inserted into the document.
+  // The |prerender_id| must be unique per |child_id|, and is typically
+  // assigned by the WebPrerendererClient.

[dominich, 2012/04/30 15:52:05]

Is it ever not assigned by the WebPrerendererClient?

[gavinp, 2012/04/30 23:55:39]

No, never.  Fixed.

+  // Returns true if the prerender was accepted by the prerender manager,
+  // and false if not.  In either case, the |prerender_id| is usable for
+  // future OnCancelPrerender and OnAbandonPrerender calls.
+  bool OnAddPrerender(
+      int child_id,
+      int prerender_id,
+      const GURL& url,
+      const content::Referrer& referrer,
+      const gfx::Size& size,
+      int render_view_route_id);
+
+  // A <link rel=prerender ...> element has been explicitly removed from a
+  // document.
+  void OnCancelPrerender(int prerender_id, int child_id);

[mmenke, 2012/04/30 18:35:22]

nit swap argument order, here and below.

[gavinp, 2012/04/30 23:55:39]

Yes.  Thanks for catching this; I should have done this in a previous review. 
:( 

Now done.

+
+  // A renderer launching <link rel=prerender ...> has navigated away from the
+  // launching page, the launching renderer process has crashed, or perhaps the
+  // renderer process was fast-closed when the last render view in it was
+  // closed.
+  void OnAbandonPrerender(int prerender_id, int child_id);
+
+  // If a renderer channel closes (crash, fast exit, etc...), that's effectively
+  // an abandon of any prerenders launched by that child.
+  void OnChannelClosing(int child_id);
+
+ private:
+  FRIEND_TEST_ALL_PREFIXES(PrerenderBrowserTest, PrerenderPage);
+  FRIEND_TEST_ALL_PREFIXES(PrerenderBrowserTest, PrerenderPageRemovingLink);
+  FRIEND_TEST_ALL_PREFIXES(PrerenderBrowserTest,
+                           PrerenderPageRemovingLinkWithTwoLinks);
+  FRIEND_TEST_ALL_PREFIXES(PrerenderBrowserTest,
+                           PrerenderPageRemovingLinkWithTwoLinksRemovingOne);
+  friend class PrerenderTest;
+
+  typedef std::pair<int, int> ChildAndPrerenderIdPair;
+  typedef std::map<ChildAndPrerenderIdPair, GURL> IdPairToUrlMap;
+  typedef std::multimap<GURL, ChildAndPrerenderIdPair> UrlToIdPairMap;

[dominich, 2012/04/30 15:52:05]

This type isn't used any more, is it?

[gavinp, 2012/04/30 23:55:39]

Done.

+
+  void RemovePrerender(const IdPairToUrlMap::iterator& id_url_iter);
+
+  bool IsEmpty() const;
+
+  PrerenderManager* manager_;
+  IdPairToUrlMap ids_to_url_map_;
+
+  DISALLOW_COPY_AND_ASSIGN(PrerenderLinkManager);
+};
+
+}  // namespace prerender
+
+#endif  // CHROME_BROWSER_PRERENDER_PRERENDER_LINK_MANAGER_H_
+