Fix mouse wheel scrolling on PDFs.

third_party/WebKit/Source/web/WebViewImpl.h

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 597 matching lines @@
     void handleMouseUp(LocalFrame&, const WebMouseEvent&) override;
     WebInputEventResult handleMouseWheel(LocalFrame&, const WebMouseWheelEvent&) override;
     WebInputEventResult handleGestureEvent(const WebGestureEvent&) override;
     WebInputEventResult handleKeyEvent(const WebKeyboardEvent&) override;
     WebInputEventResult handleCharEvent(const WebKeyboardEvent&) override;
 
     WebInputEventResult handleSyntheticWheelFromTouchpadPinchEvent(const WebGestureEvent&);
 
     WebPlugin* focusedPluginIfInputMethodSupported(LocalFrame*);
 
+    WebGestureEvent createGestureScrollEventFromFling(WebInputEvent::Type, WebGestureDevice) const;
+
     void enablePopupMouseWheelEventListener();
     void disablePopupMouseWheelEventListener();
 
     void cancelPagePopup();
     void updatePageOverlays();
 
     float deviceScaleFactor() const;
 
     WebViewClient* m_client; // Can be 0 (e.g. unittests, shared workers, etc.)
     WebSpellCheckClient* m_spellCheckClient;
@@ skipping 141 matching lines @@
 };
 
 DEFINE_TYPE_CASTS(WebViewImpl, WebWidget, widget, widget->isWebView(), widget.isWebView());
 // We have no ways to check if the specified WebView is an instance of
 // WebViewImpl because WebViewImpl is the only implementation of WebView.
 DEFINE_TYPE_CASTS(WebViewImpl, WebView, webView, true, true);
 
 } // namespace blink
 
 #endif