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

chrome/browser/extensions/favicon_downloader.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_EXTENSIONS_FAVICON_DOWNLOADER_H_
+#define CHROME_BROWSER_EXTENSIONS_FAVICON_DOWNLOADER_H_
+
+#include <map>
+#include <set>
+#include <vector>
+
+#include "base/callback.h"
+#include "base/memory/weak_ptr.h"
+#include "content/public/browser/web_contents_observer.h"
+
+class SkBitmap;
+
+namespace content {
+struct FaviconURL;
+}
+
+namespace gfx {
+class Size;
+}
+
+// Class to help download all favicons for a tab.
+class FaviconDownloader : public content::WebContentsObserver {
+ public:
+  typedef std::map<GURL, std::vector<SkBitmap> > FaviconMap;
+  typedef base::Callback<void(
+          bool,  /* success */
+          /* A map of icon urls to the bitmaps provided by that url. */
+          const FaviconMap&)>
+      FaviconDownloaderCallback;
+  // |extra_favicon_urls| allows callers to provide icon urls that aren't
+  // |provided by the renderer (e.g touch icons on non-android environments).
+  FaviconDownloader(content::WebContents* web_contents,
+                    const std::vector<GURL>& extra_favicon_urls,
+                    FaviconDownloaderCallback callback);
+  virtual ~FaviconDownloader();
+
+  void Start();
+
+ private:
+  friend class TestFaviconDownloader;
+
+  // Initiates a download of the image at |url| and returns the download id.
+  // This is overridden in testing.
+  virtual int DownloadImage(const GURL& url);
+
+  // Queries FaviconTabHelper for the page's current favicon URLs.
+  // This is overridden in testing.
+  virtual std::vector<content::FaviconURL> GetFaviconURLsFromWebContents();
+
+  // Fetches icons for the given urls.
+  // |callback_| is run when all downloads complete.
+  void FetchIcons(const std::vector<content::FaviconURL>& favicon_urls);
+  void FetchIcons(const std::vector<GURL>& urls);
+
+  // Icon download callback.
+  void DidDownloadFavicon(int id,
+                          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;
+
+  // Whether we have received favicons from the renderer.
+  bool got_favicon_urls_;
+
+  // URLs that aren't given by WebContentsObserver::DidUpdateFaviconURL() that
+  // should be used for this favicon. This is necessary in order to get touch
+  // icons on non-android environments.
+  std::vector<GURL> extra_favicon_urls_;
+
+  // The icons which were downloaded. Populated by FetchIcons().
+  FaviconMap favicon_map_;
+
+  // Request ids of in-progress requests.
+  std::set<int> in_progress_requests_;
+
+  // Urls for which a download has already been initiated. Used to prevent
+  // duplicate downloads of the same url.
+  std::set<GURL> processed_urls_;
+
+  // Callback to run on favicon download completion.
+  FaviconDownloaderCallback callback_;
+
+  base::WeakPtrFactory<FaviconDownloader> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(FaviconDownloader);
+};
+
+#endif  // CHROME_BROWSER_EXTENSIONS_FAVICON_DOWNLOADER_H_