Introduce InfoBarTabService API.

chrome/browser/api/infobars/infobar_tab_service.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_API_INFOBARS_INFOBAR_TAB_SERVICE_H_
+#define CHROME_BROWSER_API_INFOBARS_INFOBAR_TAB_SERVICE_H_
+
+namespace content {
+class WebContents;
+}
+
+class InfoBarDelegate;
+class TabContents;
+
+// Provides access to creating, removing and enumerating info bars
+// attached to a tab.
+class InfoBarTabService {
+ public:
+  // Retrieves the InfoBarTabService for a given tab.
+  static InfoBarTabService* GetInstance(TabContents* tab_contents);

[tfarina, 2012/08/16 12:14:35]

According to crbug.com/68682 static methods should be after virtual destructors.
But I agree that separating static from virtuals in interfaces like this, looks
better ;)

[Jói, 2012/08/16 12:23:33]

Thanks, putting them at the top like this, at least if they are factory or
retrieval methods, has been the convention in content/.

[erikwright (departed), 2012/08/16 17:25:38]

My comments elsewhere apply here. I don't think that a conforming component
should use this API. Perhaps move it out of /api/.

[Jói, 2012/08/17 15:51:24]

As per discussion summarized in http://codereview.chromium.org/10828345/ we
decided this is staying and the pattern is allowed in /api/ but we may revisit
this later and apply dependency injection more broadly.

+
+  virtual ~InfoBarTabService() {}
+
+  // Adds an InfoBar for the specified |delegate|.
+  //
+  // If infobars are disabled for this tab or the tab already has a delegate
+  // which returns true for InfoBarDelegate::EqualsDelegate(delegate),
+  // |delegate| is closed immediately without being added.
+  //
+  // Returns whether |delegate| was successfully added.
+  virtual bool AddInfoBar(InfoBarDelegate* delegate) = 0;
+
+  // Removes the InfoBar for the specified |delegate|.
+  //
+  // If infobars are disabled for this tab, this will do nothing, on the
+  // assumption that the matching AddInfoBar() call will have already closed the
+  // delegate (see above).
+  virtual void RemoveInfoBar(InfoBarDelegate* delegate) = 0;
+
+  // Replaces one infobar with another, without any animation in between.
+  //
+  // If infobars are disabled for this tab, |new_delegate| is closed immediately
+  // without being added, and nothing else happens.
+  //
+  // Returns whether |new_delegate| was successfully added.
+  //
+  // NOTE: This does not perform any EqualsDelegate() checks like AddInfoBar().
+  virtual bool ReplaceInfoBar(InfoBarDelegate* old_delegate,
+                              InfoBarDelegate* new_delegate) = 0;
+
+  // Returns the number of infobars for this tab.
+  virtual size_t GetInfoBarCount() const = 0;
+
+  // Returns the infobar at the given |index|.
+  //
+  // Warning: Does not sanity check |index|.
+  virtual InfoBarDelegate* GetInfoBarDelegateAt(size_t index) = 0;
+
+  // Retrieve the WebContents for the tab this service is associated with.
+  virtual content::WebContents* GetWebContents() = 0;
+};
+
+#endif  // CHROME_BROWSER_API_INFOBARS_INFOBAR_TAB_SERVICE_H_