Upstream Chrome on iOS source code [9/11].

ios/chrome/browser/ui/tab_switcher/tab_switcher_utils.h

+// Copyright 2015 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 IOS_CHROME_BROWSER_UI_TAB_SWITCHER_TAB_SWITCHER_UTILS_H_
+#define IOS_CHROME_BROWSER_UI_TAB_SWITCHER_TAB_SWITCHER_UTILS_H_
+
+#include <vector>
+
+class GURL;
+@class UIImage;
+namespace ios {
+class ChromeBrowserState;
+}  // namespace ios
+
+namespace ios_internal {
+
+typedef void (^FaviconGetterCompletionBlock)(UIImage*);
+
+// Favicon for |url|, calls |block| when loaded.
+void GetFavicon(GURL const& url,
+                ios::ChromeBrowserState* browserState,
+                FaviconGetterCompletionBlock block);
+
+// Returns the substitutions/deletions/insertions needed to go from |initial| to
+// |final|.
+// To be in accordance with the UICollectionView's |performBatchUpdates| method:
+// -the indexes in |substitutions| are relative to |initial|.
+// -the indexes in |deletions| are relative to |initial|.
+// -the indexes in |insertions| are relative to |final|.
+//
+// The returned sequence is chosen with a preference of insertions and deletions
+// over substitutions.
+// For example, AB => BC could be done with 2 substitutions, but doing
+// 1 insertion and 1 deletion is preferable because it better communicates the
+// changes to the user in the UICollectionViews.
+void MinimalReplacementOperations(std::vector<size_t> const& initial,
+                                  std::vector<size_t> const& final,
+                                  std::vector<size_t>* substitutions,
+                                  std::vector<size_t>* deletions,
+                                  std::vector<size_t>* insertions);
+
+}  // namespace ios_internal
+
+#endif  // IOS_CHROME_BROWSER_UI_TAB_SWITCHER_TAB_SWITCHER_UTILS_H_