Adds support for showing the match preview on views. It's behind the

chrome/browser/tabs/tab_strip_model.h

 // Copyright (c) 2010 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_TABS_TAB_STRIP_MODEL_H_
 #define CHROME_BROWSER_TABS_TAB_STRIP_MODEL_H_
 #pragma once
 
 #include <vector>
 
@@ skipping 36 matching lines @@
     // Only the loading state changed.
     LOADING_ONLY,
 
     // Only the title changed and page isn't loading.
     TITLE_NOT_LOADING,
 
     // Change not characterized by LOADING_ONLY or TITLE_NOT_LOADING.
     ALL
   };
 
+  // Enum used by ReplaceTabContentsAt.
+  // TODO(sky): TabReplaceType should be declared outside the scope of
+  // the observer. I need to put all the enums in a namespace and cleanup this
+  // file.
+  enum TabReplaceType {
+    // The replace is the result of the tab being made phantom.
+    REPLACE_MADE_PHANTOM,
+
+    // The replace is the result of the match preview being committed.
+    REPLACE_MATCH_PREVIEW
+  };
+
   // A new TabContents was inserted into the TabStripModel at the specified
   // index. |foreground| is whether or not it was opened in the foreground
   // (selected).
   virtual void TabInsertedAt(TabContents* contents,
                              int index,
                              bool foreground);
 
   // The specified TabContents at |index| is being closed (and eventually
   // destroyed).
   virtual void TabClosingAt(TabContents* contents, int index);
@@ skipping 26 matching lines @@
   // be an entirely different object and the old value is no longer available
   // by the time this message is delivered.
   //
   // See TabChangeType for a description of |change_type|.
   virtual void TabChangedAt(TabContents* contents, int index,
                             TabChangeType change_type);
 
   // The tab contents was replaced at the specified index. This is invoked when
   // a tab becomes phantom. See description of phantom tabs in class description
   // of TabStripModel for details.
+  // TODO(sky): nuke this in favor of the 4 arg variant.
   virtual void TabReplacedAt(TabContents* old_contents,
-                             TabContents* new_contents, int index);
+                             TabContents* new_contents,
+                             int index);
+
+  // The tab contents was replaced at the specified index. |type| describes
+  // the type of replace.
+  // This invokes TabReplacedAt with three args.
+  virtual void TabReplacedAt(TabContents* old_contents,
+                             TabContents* new_contents,
+                             int index,
+                             TabReplaceType type);
 
   // Invoked when the pinned state of a tab changes. This is not invoked if the
   // tab ends up moving as a result of the mini state changing.
   // See note in TabMiniStateChanged as to how this relates to
   // TabMiniStateChanged.
   virtual void TabPinnedStateChanged(TabContents* contents, int index);
 
   // Invoked if the mini state of a tab changes.  This is not invoked if the
   // tab ends up moving as a result of the mini state changing.
   // NOTE: this is sent when the pinned state of a non-app tab changes and is
@@ skipping 311 matching lines @@
   // Replaces the entire state of a the tab at index by switching in a
   // different NavigationController. This is used through the recently
   // closed tabs list, which needs to replace a tab's current state
   // and history with another set of contents and history.
   //
   // The old NavigationController is deallocated and this object takes
   // ownership of the passed in controller.
   void ReplaceNavigationControllerAt(int index,
                                      NavigationController* controller);
 
+  // Replaces the tab contents at |index| with |new_contents|. |type| is passed
+  // to the observer. This deletes the TabContents currently at |index|.
+  void ReplaceTabContentsAt(int index,
+                            TabContents* new_contents,
+                            TabStripModelObserver::TabReplaceType type);
+
   // Detaches the TabContents at the specified index from this strip. The
   // TabContents is not destroyed, just removed from display. The caller is
   // responsible for doing something with it (e.g. stuffing it into another
   // strip).
   TabContents* DetachTabContentsAt(int index);
 
   // Select the TabContents at the specified index. |user_gesture| is true if
   // the user actually clicked on the tab or navigated to it using a keyboard
   // command, false if the tab was selected as a by-product of some other
   // action.
@@ skipping 272 matching lines @@
                              bool select_after_move);
 
   // Returns true if the tab represented by the specified data has an opener
   // that matches the specified one. If |use_group| is true, then this will
   // fall back to check the group relationship as well.
   struct TabContentsData;
   static bool OpenerMatches(const TabContentsData* data,
                             const NavigationController* opener,
                             bool use_group);
 
+  // Does the work for ReplaceTabContentsAt returning the old TabContents.
+  // The caller owns the returned TabContents.
+  TabContents* ReplaceTabContentsAtImpl(
+      int index,
+      TabContents* new_contents,
+      TabStripModelObserver::TabReplaceType type);
+
   // Our delegate.
   TabStripModelDelegate* delegate_;
 
   // A hunk of data representing a TabContents and (optionally) the
   // NavigationController that spawned it. This memory only sticks around while
   // the TabContents is in the current TabStripModel, unless otherwise
   // specified in code.
   struct TabContentsData {
     explicit TabContentsData(TabContents* a_contents)
         : contents(a_contents),
@@ skipping 69 matching lines @@
   typedef ObserverList<TabStripModelObserver> TabStripModelObservers;
   TabStripModelObservers observers_;
 
   // A scoped container for notification registries.
   NotificationRegistrar registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(TabStripModel);
 };
 
 #endif  // CHROME_BROWSER_TABS_TAB_STRIP_MODEL_H_