Add PlatformFrameView class.

third_party/WebKit/Source/core/loader/EmptyClients.h

Index: third_party/WebKit/Source/core/loader/EmptyClients.h
diff --git a/third_party/WebKit/Source/core/loader/EmptyClients.h b/third_party/WebKit/Source/core/loader/EmptyClients.h
index 2cc4874e780cb5163696e9798c6314a8cc9c7838..12cef194cfb2d1b671c61224028349b2e1c1c48b 100644
--- a/third_party/WebKit/Source/core/loader/EmptyClients.h
+++ b/third_party/WebKit/Source/core/loader/EmptyClients.h
@@ -169,10 +169,10 @@ class CORE_EXPORT EmptyChromeClient : public ChromeClient {
   bool TabsToLinks() override { return false; }
 
   void InvalidateRect(const IntRect&) override {}
-  void ScheduleAnimation(LocalFrame*) override {}
+  void ScheduleAnimation(const PlatformFrameView*) override {}
 
   IntRect ViewportToScreen(const IntRect& r,
-                           const FrameViewBase*) const override {
+                           const PlatformFrameView*) const override {
     return r;
   }
   float WindowToViewportScalar(const float s) const override { return s; }