Use high resolution icons where possible for streamlined hosted app icons.

chrome/browser/ui/web_applications/hosted_app_tab_helper.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_UI_WEB_APPLICATIONS_HOSTED_APP_TAB_HELPER_H_
+#define CHROME_BROWSER_UI_WEB_APPLICATIONS_HOSTED_APP_TAB_HELPER_H_
+
+#include <set>
+#include <vector>
+
+#include "base/memory/scoped_ptr.h"
+#include "content/public/browser/web_contents_observer.h"
+#include "content/public/browser/web_contents_user_data.h"
+#include "ui/gfx/image/image_family.h"
+
+class HostedAppTabHelperDelegate;
+class SkBitmap;
+struct WebApplicationInfo;
+
+namespace content {
+struct FaviconURL;
+}
+
+namespace gfx {
+class Size;
+}
+
+// Per-tab class to help manage hosted app taskbar icons.

[benwells, 2013/11/13 21:55:17]

Nit: this does more than manage hosted app icons, it creates hosted apps. If it
is just about getting a wider variety of icons we should make it a more general
thing (e.g. MultiSizeFaviconTabHelper, FaviconFamilyTabHelper).

[calamity, 2013/11/15 04:25:50]

Fixed comment. This will also be where we update the generated hosted app (if
that's something we want to do).

+class HostedAppTabHelper
+    : public content::WebContentsObserver,
+      public content::WebContentsUserData<HostedAppTabHelper> {
+ public:
+  virtual ~HostedAppTabHelper();
+
+  // Creates a hosted app for |web_app_info| using the current tab's icons.
+  void CreateHostedApp(const WebApplicationInfo& web_app_info);
+
+  // Sets a delegate to notify on icon load. |fetch_icons_immediately| decides
+  // whether icons are fetched as soon as a page loads, rather than when
+  // CreateHostedApp() is called.
+  void SetDelegate(HostedAppTabHelperDelegate* delegate,
+                   bool fetch_icons_immediately);
+
+  const gfx::ImageFamily& image_family() {
+    return image_family_;
+  }
+
+  size_t pending_requests() { return in_progress_requests_.size(); }

[tapted, 2013/11/13 07:44:53]

nit: can probably declare this function const

[calamity, 2013/11/15 04:25:50]

Done.

+
+  // Icon download callback.
+  void DidDownloadFavicon(int id,

[tapted, 2013/11/13 07:44:53]

nit: should this and the overrides be in private?

[calamity, 2013/11/15 04:25:50]

They need to be public so the tests can use them to poke at the class.

+                          int http_status_code,
+                          const GURL& image_url,
+                          const std::vector<SkBitmap>& bitmaps,
+                          const std::vector<gfx::Size>& original_bitmap_sizes);
+
+  // content::WebContentsObserver overrides:
+  virtual void DidNavigateMainFrame(
+      const content::LoadCommittedDetails& details,
+      const content::FrameNavigateParams& params) OVERRIDE;
+  virtual void DidUpdateFaviconURL(
+      int32 page_id,
+      const std::vector<content::FaviconURL>& candidates) OVERRIDE;
+
+ protected:
+  // These are used for testing.
+
+  explicit HostedAppTabHelper(content::WebContents* web_contents);

[benwells, 2013/11/13 21:55:17]

Nit - remove blank line above.
Nit - is 'they' all the protected things? If so
/DownloadImage/DownloadImageForTesting/. If not /are used for/are protected to
be overridden in/.

[calamity, 2013/11/15 04:25:50]

The tests switch out the definition of DownloadImage. There is a real
implementation in hosted_app_tab_helper.cc which actually downloads an image.
The testing implementation just returns incrementing ids.

+
+  // Downloads |url| and adds the download id to |in_progress_requests_|.
+  virtual int DownloadImage(const GURL& url);
+
+ private:
+  friend class content::WebContentsUserData<HostedAppTabHelper>;
+
+  // Fetches the icons in |favicon_url_candidates_|. Downloads are handled in
+  // DidDownloadFavicon.
+  void FetchIcons();
+
+  // Fetches icons for creating the hosted app from |favicon_url_candidates| and
+  // |web_app_info_.icons|. FinishCreateHostedApp() is called on completion.
+  void FetchIconsIfNecessaryForCreateHostedApp();
+
+  // Creates and installs the hosted app for |web_app_info_|.
+  void FinishCreateHostedApp();
+
+  // Candidate favicon URLs for the current page. Repopulated each page load.
+  scoped_ptr<std::set<GURL> > favicon_url_candidates_;
+
+  // The current page's icons. Populated by FetchIcons() or CreateHostedApp().
+  gfx::ImageFamily image_family_;
+
+  // Info of a web app to create a hosted app for.
+  scoped_ptr<WebApplicationInfo> web_app_info_;
+
+  // Request ids of in-progress requests.
+  std::set<int> in_progress_requests_;
+
+  // Whether we should fetch icons as soon as the |favicon_url_candidates_| are
+  // updated.
+  bool fetch_icons_immediately_;
+
+  HostedAppTabHelperDelegate* delegate_;
+
+  DISALLOW_COPY_AND_ASSIGN(HostedAppTabHelper);
+};
+
+#endif  // CHROME_BROWSER_UI_WEB_APPLICATIONS_HOSTED_APP_TAB_HELPER_H_