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

chrome/browser/tabs/tab_strip_model.cc

 // 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.
 
 #include "chrome/browser/tabs/tab_strip_model.h"
 
 #include <algorithm>
 
 #include "base/command_line.h"
 #include "base/stl_util-inl.h"
@@ skipping 64 matching lines @@
 
 void TabStripModelObserver::TabChangedAt(TabContents* contents, int index,
                                          TabChangeType change_type) {
 }
 
 void TabStripModelObserver::TabReplacedAt(TabContents* old_contents,
                                           TabContents* new_contents,
                                           int index) {
 }
 
+void TabStripModelObserver::TabReplacedAt(TabContents* old_contents,
+                                          TabContents* new_contents,
+                                          int index,
+                                          TabReplaceType type) {
+  TabReplacedAt(old_contents, new_contents, index);
+}
+
 void TabStripModelObserver::TabPinnedStateChanged(TabContents* contents,
                                                   int index) {
 }
 
 void TabStripModelObserver::TabMiniStateChanged(TabContents* contents,
                                                 int index) {
 }
 
 void TabStripModelObserver::TabBlockedStateChanged(TabContents* contents,
                                                    int index) {
@@ skipping 131 matching lines @@
     ++selected_index_;
   }
 
   FOR_EACH_OBSERVER(TabStripModelObserver, observers_,
       TabInsertedAt(contents, index, foreground));
 
   if (foreground)
     ChangeSelectedContentsFrom(selected_contents, index, false);
 }
 
+void TabStripModel::ReplaceTabContentsAt(
+    int index,
+    TabContents* new_contents,
+    TabStripModelObserver::TabReplaceType type) {
+  delete ReplaceTabContentsAtImpl(index, new_contents, type);
+}
+
 void TabStripModel::ReplaceNavigationControllerAt(
     int index, NavigationController* controller) {
   // This appears to be OK with no flicker since no redraw event
   // occurs between the call to add an aditional tab and one to close
   // the previous tab.
   InsertTabContentsAt(
       index + 1, controller->tab_contents(),
       ADD_SELECTED | ADD_INHERIT_GROUP);
   std::vector<int> closing_tabs;
   closing_tabs.push_back(index);
@@ skipping 790 matching lines @@
     DCHECK(extension_app);
 
     // Only allow the tab to be made phantom if the extension still exists.
     return extension_service->GetExtensionById(extension_app->id(),
                                                false) != NULL;
   }
   return false;
 }
 
 void TabStripModel::MakePhantom(int index) {
-  TabContents* old_contents = GetContentsAt(index);
-  TabContents* new_contents = old_contents->CloneAndMakePhantom();
-
-  contents_data_[index]->contents = new_contents;
-
-  // And notify observers.
-  FOR_EACH_OBSERVER(TabStripModelObserver, observers_,
-                    TabReplacedAt(old_contents, new_contents, index));
+  // MakePhantom is called when the TabContents is being destroyed so we don't
+  // need to do anything with the returned value from ReplaceTabContentsAtImpl.
+  ReplaceTabContentsAtImpl(index, GetContentsAt(index)->CloneAndMakePhantom(),
+                           TabStripModelObserver::REPLACE_MADE_PHANTOM);
 
   if (selected_index_ == index && HasNonPhantomTabs()) {
     // Change the selection, otherwise we're going to force the phantom tab
     // to become selected.
     // NOTE: we must do this after the call to Replace otherwise browser's
     // TabSelectedAt will send out updates for the old TabContents which we've
     // already told observers has been closed (we sent out TabClosing at).
     int new_selected_index =
         order_controller_->DetermineNewSelectedIndex(index, false);
     new_selected_index = IndexOfNextNonPhantomTab(new_selected_index,
@@ skipping 24 matching lines @@
   FOR_EACH_OBSERVER(TabStripModelObserver, observers_,
                     TabMoved(moved_data->contents, index, to_position));
 }
 
 // static
 bool TabStripModel::OpenerMatches(const TabContentsData* data,
                                   const NavigationController* opener,
                                   bool use_group) {
   return data->opener == opener || (use_group && data->group == opener);
 }
+
+TabContents* TabStripModel::ReplaceTabContentsAtImpl(
+    int index,
+    TabContents* new_contents,
+    TabStripModelObserver::TabReplaceType type) {
+  // TODO: this should reset group/opener of any tabs that point at
+  // old_contents.
+  DCHECK(ContainsIndex(index));
+
+  TabContents* old_contents = GetContentsAt(index);
+
+  contents_data_[index]->contents = new_contents;
+
+  FOR_EACH_OBSERVER(TabStripModelObserver, observers_,
+                    TabReplacedAt(old_contents, new_contents, index, type));
+  return old_contents;
+}