[Extensions] Remove ExtensionFunction usage of RenderViewHost

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 f7d686913588e38a24801ab5de415c0b1e4454ae..5bd7d1976971e765c79641bb7295df75c6aebbcc 100644
--- a/extensions/browser/guest_view/web_view/web_view_guest.h
+++ b/extensions/browser/guest_view/web_view/web_view_guest.h
@@ -181,6 +181,7 @@ class WebViewGuest : public guest_view::GuestView<WebViewGuest>,
                  const gfx::Rect& selection_rect,
                  int active_match_ordinal,
                  bool final_update) final;
+  bool ZoomPropagatesFromEmbedderToGuest() const final;
   const char* GetAPINamespace() const final;
   int GetTaskPrefix() const final;
   void GuestDestroyed() final;
@@ -377,6 +378,9 @@ class WebViewGuest : public guest_view::GuestView<WebViewGuest>,
   // navigation. This will be equal to 0 when there is no pending zoom.
   double pending_zoom_factor_;
 
+  // Whether the GuestView set an explicit zoom level.
+  bool did_set_explicit_zoom_;
+
   // This is used to ensure pending tasks will not fire after this object is
   // destroyed.
   base::WeakPtrFactory<WebViewGuest> weak_ptr_factory_;