Cleanup: Remove unused variables in chrome/ found by Scythe.

chrome/browser/ui/search/instant_page.h

Index: chrome/browser/ui/search/instant_page.h
diff --git a/chrome/browser/ui/search/instant_page.h b/chrome/browser/ui/search/instant_page.h
index e3cc6bbc729e5ad8ee65e6aafa655e500ed02e60..1ff7bc394f5ee6d21633e816daf5dd804be6203e 100644
--- a/chrome/browser/ui/search/instant_page.h
+++ b/chrome/browser/ui/search/instant_page.h
@@ -71,8 +71,9 @@ class InstantPage : public content::WebContentsObserver,
   virtual bool IsLocal() const;
 
  protected:
-  InstantPage(Delegate* delegate, const std::string& instant_url,
-              Profile* profile, bool is_incognito);
+  InstantPage(Delegate* delegate,
+              const std::string& instant_url,
+              Profile* profile);
 
   // Sets |web_contents| as the page to communicate with. |web_contents| may be
   // NULL, which effectively stops all communication.
@@ -119,7 +120,6 @@ class InstantPage : public content::WebContentsObserver,
 
   Delegate* const delegate_;
   const std::string instant_url_;
-  const bool is_incognito_;
 
   DISALLOW_COPY_AND_ASSIGN(InstantPage);
 };