Instant: Use only one hidden WebContents per profile.

chrome/browser/infobars/infobar_container.h

Index: chrome/browser/infobars/infobar_container.h
diff --git a/chrome/browser/infobars/infobar_container.h b/chrome/browser/infobars/infobar_container.h
index c1b6633bbc38fe078736d76c3fc19aaf5c20bf77..4cfd3644b264e8ca3e93a1d78e5101d576c7f319 100644
--- a/chrome/browser/infobars/infobar_container.h
+++ b/chrome/browser/infobars/infobar_container.h
@@ -38,7 +38,7 @@ class SearchModel;
 // temporarily if the user changes into |SEARCH_SUGGESTIONS| mode (refer to
 // chrome::search::Mode in chrome/common/search_types.h for all search modes)
 // when on a :
-// - |DEFAULT| page: when instant preview is ready;
+// - |DEFAULT| page: when Instant overlay is ready;
 // - |NTP| or |SEARCH_RESULTS| page: immediately;
 //   TODO(kuan): this scenario requires more complex synchronization with
 //   renderer SearchBoxAPI and will be implemented as the next step;
@@ -51,7 +51,7 @@ class SearchModel;
 // to re-hide infobars without animation is canceled if a tab change occurs.
 class InfoBarContainer : public content::NotificationObserver,
                          public chrome::search::SearchModelObserver,
-                         public InstantModelObserver  {
+                         public InstantModelObserver {
  public:
   class Delegate {
    public:
@@ -111,7 +111,7 @@ class InfoBarContainer : public content::NotificationObserver,
   const Delegate* delegate() const { return delegate_; }
 
   // InstantModelObserver:
-  virtual void PreviewStateChanged(const InstantModel& model) OVERRIDE;
+  virtual void OverlayStateChanged(const InstantModel& model) OVERRIDE;
 
  protected:
   // Subclasses must call this during destruction, so that we can remove