InstantExtended: Transient naventry for preview.

chrome/browser/instant/instant_controller.h

Index: chrome/browser/instant/instant_controller.h
diff --git a/chrome/browser/instant/instant_controller.h b/chrome/browser/instant/instant_controller.h
index db74de89ada7713558703d7d1b2a35b5a662f7f4..8d2253b9966d93e636298c361b305b26781f59af 100644
--- a/chrome/browser/instant/instant_controller.h
+++ b/chrome/browser/instant/instant_controller.h
@@ -36,6 +36,7 @@ class BrowserInstantController;
 }
 
 namespace content {
+class NavigationEntry;
 class WebContents;
 }
 
@@ -225,6 +226,18 @@ class InstantController {
                   int height,
                   InstantSizeUnits units);
 
+  // Copies the loader's active NavigationEntry into a transient history entry
+  // for the active tab. Used to update the tab title and make the back button
+  // work as expected when the preview is shown at full height but not yet
+  // committed.
+  void SetTransientHistoryEntry();
+
+  // Updates the url in the transient history entry for the overlay.

[sreeram, 2013/01/25 21:28:02]

Nit: url -> URL

+  void UpdateTransientHistoryEntry(const GURL& url);
+
+  // Restores the old transient entry for the active tab, if any.
+  void ResetTransientHistoryEntry();
+
   // Send the omnibox popup bounds to the page.
   void SendPopupBoundsToPage();
 
@@ -327,6 +340,13 @@ class InstantController {
   // MODE_SEARCH_SUGGESTIONS, except in those cases where this is false.
   bool allow_preview_to_show_search_suggestions_;
 
+  // The transient navigation entry associated with the active tab before
+  // we clobbered it for the overlay.
+  scoped_ptr<content::NavigationEntry> saved_transient_entry_;
+
+  // True iff Instant has set a transient history entry for the active tab.
+  bool instant_set_transient_entry_;
+
   DISALLOW_COPY_AND_ASSIGN(InstantController);
 };