Instant: Use only one hidden WebContents per profile.

chrome/browser/instant/instant_ntp.h

-// Copyright 2013 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_INSTANT_INSTANT_NTP_H_
-#define CHROME_BROWSER_INSTANT_INSTANT_NTP_H_
-
-#include <string>
-
-#include "base/basictypes.h"
-#include "base/compiler_specific.h"
-#include "base/memory/scoped_ptr.h"
-#include "chrome/browser/instant/instant_loader.h"
-#include "chrome/browser/instant/instant_page.h"
-
-class Profile;
-
-// InstantNTP is used to preload an Instant page that will be swapped in when a
-// user navigates to a New Tab Page (NTP). The InstantNTP contents are never
-// shown in an un-committed state.
-class InstantNTP : public InstantPage,
-                   public InstantLoader::Delegate {
- public:
-  InstantNTP(InstantPage::Delegate* delegate, const std::string& instant_url);
-  virtual ~InstantNTP();
-
-  // Creates a new WebContents and loads |instant_url_| into it. Uses
-  // |active_tab|, if non-NULL, to initialize the size of the WebContents.
-  // |on_stale_callback| will be called when |loader_| determines the page to
-  // be stale.
-  void InitContents(Profile* profile,
-                    const content::WebContents* active_tab,
-                    const base::Closure& on_stale_callback);
-
-  // Releases the WebContents for the Instant page.  This should be called when
-  // the page is about to be committed.
-  scoped_ptr<content::WebContents> ReleaseContents() WARN_UNUSED_RESULT;
-
-  // Returns the URL that we're loading.
-  const std::string& instant_url() const { return instant_url_; }
-
- private:
-  // Overriden from InstantLoader::Delegate:
-  virtual void OnSwappedContents() OVERRIDE;
-  virtual void OnFocus() OVERRIDE;
-  virtual void OnMouseDown() OVERRIDE;
-  virtual void OnMouseUp() OVERRIDE;
-  virtual content::WebContents* OpenURLFromTab(
-      content::WebContents* source,
-      const content::OpenURLParams& params) OVERRIDE;
-
-  // Overridden from InstantPage:
-  virtual bool ShouldProcessRenderViewCreated() OVERRIDE;
-  virtual bool ShouldProcessRenderViewGone() OVERRIDE;
-
-  InstantLoader loader_;
-  const std::string instant_url_;
-
-  DISALLOW_COPY_AND_ASSIGN(InstantNTP);
-};
-
-#endif  // CHROME_BROWSER_INSTANT_INSTANT_NTP_H_