Move ZoomController out of ChromeWebViewGuestDelegate.

extensions/browser/guest_view/web_view/web_view_guest.h

Index: extensions/browser/guest_view/web_view/web_view_guest.h
diff --git a/extensions/browser/guest_view/web_view/web_view_guest.h b/extensions/browser/guest_view/web_view/web_view_guest.h
index 3ca4753b2c5cde69f63643a13626b0cb680fce98..433d111f08ace5bcb40fd691283237e223e24877 100644
--- a/extensions/browser/guest_view/web_view/web_view_guest.h
+++ b/extensions/browser/guest_view/web_view/web_view_guest.h
@@ -174,7 +174,7 @@ class WebViewGuest : public GuestView<WebViewGuest>,
                const content::NotificationDetails& details) override;
 
   // Returns the current zoom factor.
-  double GetZoom();
+  double zoom() const { return current_zoom_factor_; }
 
   // Begin or continue a find request.
   void StartFinding(const base::string16& search_text,
@@ -368,6 +368,9 @@ class WebViewGuest : public GuestView<WebViewGuest>,
   typedef std::map<WebViewGuest*, NewWindowInfo> PendingWindowMap;
   PendingWindowMap pending_new_windows_;
 
+  // Stores the current zoom factor.
+  double current_zoom_factor_;
+
   // This is used to ensure pending tasks will not fire after this object is
   // destroyed.
   base::WeakPtrFactory<WebViewGuest> weak_ptr_factory_;