Allow objects without scrollbars to be scrollable

Source/core/platform/ScrollView.h

 /*
  * Copyright (C) 2004, 2006, 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Holger Hans Peter Freyther
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 28 matching lines @@
 
 class HostWindow;
 class Scrollbar;
 
 class ScrollView : public Widget, public ScrollableArea {
 public:
     ~ScrollView();
 
     // ScrollableArea functions.
     virtual int scrollSize(ScrollbarOrientation) const OVERRIDE;
-    virtual int scrollPosition(Scrollbar*) const OVERRIDE;
     virtual void setScrollOffset(const IntPoint&) OVERRIDE;
     virtual bool isScrollCornerVisible() const OVERRIDE;
     virtual void scrollbarStyleChanged(int newStyle, bool forceUpdate) OVERRIDE;
+    virtual bool userInputScrollable(ScrollbarOrientation) const OVERRIDE;
 
     virtual void notifyPageThatContentAreaWillPaint() const;
 
     // NOTE: This should only be called by the overriden setScrollOffset from ScrollableArea.
     virtual void scrollTo(const IntSize& newOffset);
 
     // The window thats hosts the ScrollView. The ScrollView will communicate scrolls and repaints to the
     // host window in the window's coordinate space.
     virtual HostWindow* hostWindow() const = 0;
 
@@ skipping 43 matching lines @@
     void setPaintsEntireContents(bool);
 
     // By default, paint events are clipped to the visible area.  If set to
     // false, paint events are no longer clipped.  paintsEntireContents() implies !clipsRepaints().
     bool clipsRepaints() const { return m_clipsRepaints; }
     void setClipsRepaints(bool);
 
     // Overridden by FrameView to create custom CSS scrollbars if applicable.
     virtual PassRefPtr<Scrollbar> createScrollbar(ScrollbarOrientation);
 
-    // If the prohibits scrolling flag is set, then all scrolling in the view (even programmatic scrolling) is turned off.
-    void setProhibitsScrolling(bool b) { m_prohibitsScrolling = b; }
-    bool prohibitsScrolling() const { return m_prohibitsScrolling; }
-
     // Whether or not a scroll view will blit visible contents when it is scrolled. Blitting is disabled in situations
     // where it would cause rendering glitches (such as with fixed backgrounds or when the view is partially transparent).
     void setCanBlitOnScroll(bool);
     bool canBlitOnScroll() const;
 
     // The visible content rect has a location that is the scrolled offset of the document. The width and height are the viewport width
     // and height. By default the scrollbars themselves are excluded from this rectangle, but an optional boolean argument allows them to be
     // included.
     virtual IntRect visibleContentRect(VisibleContentRectIncludesScrollbars = ExcludeScrollbars) const OVERRIDE;
     IntSize visibleSize() const { return visibleContentRect().size(); }
@@ skipping 173 matching lines @@
 
 private:
     RefPtr<Scrollbar> m_horizontalScrollbar;
     RefPtr<Scrollbar> m_verticalScrollbar;
     ScrollbarMode m_horizontalScrollbarMode;
     ScrollbarMode m_verticalScrollbarMode;
 
     bool m_horizontalScrollbarLock;
     bool m_verticalScrollbarLock;
 
-    bool m_prohibitsScrolling;
-
     HashSet<RefPtr<Widget> > m_children;
 
     // This bool is unused on Mac OS because we directly ask the platform widget
     // whether it is safe to blit on scroll.
     bool m_canBlitOnScroll;
 
     IntSize m_scrollOffset; // FIXME: Would rather store this as a position, but we will wait to make this change until more code is shared.
     IntPoint m_cachedScrollPosition;
     IntSize m_fixedLayoutSize;
     IntSize m_contentsSize;
@@ skipping 36 matching lines @@
     bool platformScroll(ScrollDirection, ScrollGranularity);
     void platformSetScrollbarsSuppressed(bool repaintOnUnsuppress);
     void platformRepaintContentRectangle(const IntRect&);
     bool platformIsOffscreen() const;
     void platformSetScrollbarOverlayStyle(ScrollbarOverlayStyle);
    
     void platformSetScrollOrigin(const IntPoint&, bool updatePositionAtAll, bool updatePositionSynchronously);
 
     void calculateOverhangAreasForPainting(IntRect& horizontalOverhangRect, IntRect& verticalOverhangRect);
     void updateOverhangAreas();
+
+    int pageStep(ScrollbarOrientation) const;
 }; // class ScrollView
 
 inline ScrollView* toScrollView(Widget* widget)
 {
     ASSERT(!widget || widget->isScrollView());
     return static_cast<ScrollView*>(widget);
 }
 
 inline const ScrollView* toScrollView(const Widget* widget)
 {
     ASSERT(!widget || widget->isScrollView());
     return static_cast<const ScrollView*>(widget);
 }
 
 // This will catch anyone doing an unnecessary cast.
 void toScrollView(const ScrollView*);
 
 } // namespace WebCore
 
 #endif // ScrollView_h