[ios] Moves tab_switcher code out of the ios_internal namespace.

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*);
+typedef void (^TabSwitcherFaviconGetterCompletionBlock)(UIImage*);
 
 // Favicon for |url|, calls |block| when loaded.
-void GetFavicon(GURL const& url,
-                ios::ChromeBrowserState* browserState,
-                FaviconGetterCompletionBlock block);
+void TabSwitcherGetFavicon(GURL const& url,

[rohitrao (ping after 24h), 2017/01/03 15:46:33]

This seems like a method that could move out of tab_switcher/, but I'm not sure
where it should move to.  Suggestions?

+                           ios::ChromeBrowserState* browserState,
+                           TabSwitcherFaviconGetterCompletionBlock 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
+void TabSwitcherMinimalReplacementOperations(std::vector<size_t> const& initial,

[rohitrao (ping after 24h), 2017/01/03 15:46:33]

Renamed this method to something less generic, because it's no longer in a
namespace.

+                                             std::vector<size_t> const& final,
+                                             std::vector<size_t>* substitutions,
+                                             std::vector<size_t>* deletions,
+                                             std::vector<size_t>* insertions);
 
 #endif  // IOS_CHROME_BROWSER_UI_TAB_SWITCHER_TAB_SWITCHER_UTILS_H_