Remove WebContents::IsActiveEntry from Instant Extended and from WebContents.

content/public/browser/web_contents.h

Index: content/public/browser/web_contents.h
diff --git a/content/public/browser/web_contents.h b/content/public/browser/web_contents.h
index 8a717b86dd9212e5a6b2539348155a13d8a45511..361f11e188cedc50f23bfe7dba3cf63cc5aae37b 100644
--- a/content/public/browser/web_contents.h
+++ b/content/public/browser/web_contents.h
@@ -175,7 +175,7 @@ class WebContents : public PageNavigator,
   virtual const GURL& GetVisibleURL() const = 0;
 
   // Gets the last committed URL. It represents the current page that is
-  // displayed in  this WebContents. It represents the current security
+  // displayed in this WebContents. It represents the current security
   // context.
   virtual const GURL& GetLastCommittedURL() const = 0;
 
@@ -452,9 +452,6 @@ class WebContents : public PageNavigator,
       const base::Callback<void(
           int64 /* size of the file */)>& callback) = 0;
 
-  // Returns true if the active NavigationEntry's page_id equals page_id.
-  virtual bool IsActiveEntry(int32 page_id) = 0;
-
   // Returns the contents MIME type after a navigation.
   virtual const std::string& GetContentsMimeType() const = 0;