Move CalculateScrollbarModes from FrameView to LayoutView.

third_party/WebKit/Source/core/frame/FrameView.h

 /*
    Copyright (C) 1997 Martin Jones (mjones@kde.org)
              (C) 1998 Waldo Bastian (bastian@kde.org)
              (C) 1998, 1999 Torben Weis (weis@kde.org)
              (C) 1999 Lars Knoll (knoll@kde.org)
              (C) 1999 Antti Koivisto (koivisto@kde.org)
    Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights
    reserved.
 
    This library is free software; you can redistribute it and/or
@@ skipping 46 matching lines @@
 #include "platform/wtf/HashSet.h"
 #include "platform/wtf/ListHashSet.h"
 #include "platform/wtf/text/WTFString.h"
 #include "public/platform/ShapeProperties.h"
 #include "public/platform/WebDisplayMode.h"
 #include "public/platform/WebRect.h"
 
 namespace blink {
 
 class AXObjectCache;
-class ComputedStyle;
 class Cursor;
 class DocumentLifecycle;
 class Element;
 class ElementVisibilityObserver;
 class Frame;
 class FloatSize;
 class IntRect;
 class JSONArray;
 class JSONObject;
 class LayoutItem;
@@ skipping 60 matching lines @@
     return *frame_;
   }
 
   Page* GetPage() const;
 
   // TODO(pilgrim) replace all instances of layoutView() with layoutViewItem()
   // https://crbug.com/499321
   LayoutView* GetLayoutView() const;
   LayoutViewItem GetLayoutViewItem() const;
 
+  // If false, prevents scrollbars on the viewport even if web content would
+  // make them appear. Also prevents user-input scrolls (but not programmatic
+  // scrolls).
+  // This API is root-layer-scrolling-aware (affects root PLSA in RLS mode).
   void SetCanHaveScrollbars(bool);
+  bool CanHaveScrollbars() const { return can_have_scrollbars_; }
 
   Scrollbar* CreateScrollbar(ScrollbarOrientation);
 
   void SetContentsSize(const IntSize&);
 
   void UpdateLayout();
   bool DidFirstLayout() const;
   void ScheduleRelayout();
   void ScheduleRelayoutOfSubtree(LayoutObject*);
   bool LayoutPending() const;
@@ skipping 196 matching lines @@
     kScrollable,
     kNotScrollableNoOverflow,
     kNotScrollableNotVisible,
     kNotScrollableExplicitlyDisabled
   };
 
   ScrollingReasons GetScrollingReasons() const;
   bool IsScrollable() const override;
   bool IsProgrammaticallyScrollable() override;
 
-  void CalculateScrollbarModes(ScrollbarMode& h_mode,

[szager1, 2017/05/22 18:29:35]

So confusing, thanks for getting rid of this.

-                               ScrollbarMode& v_mode) const;
-
   IntPoint LastKnownMousePosition() const override;
   bool ShouldSetCursor() const;
 
   void SetCursor(const Cursor&);
 
   bool ScrollbarsCanBeActive() const override;
   void ScrollbarVisibilityChanged() override;
   void ScrollbarFrameRectChanged() override;
 
   // FIXME: Remove this method once plugin loading is decoupled from layout.
@@ skipping 167 matching lines @@
   bool HorizontalScrollbarLock() const { return horizontal_scrollbar_lock_; }
   void SetVerticalScrollbarLock(bool lock = true) {
     vertical_scrollbar_lock_ = lock;
   }
   bool VerticalScrollbarLock() const { return vertical_scrollbar_lock_; }
 
   void SetScrollingModesLock(bool lock = true) {
     horizontal_scrollbar_lock_ = vertical_scrollbar_lock_ = lock;
   }
 
-  bool CanHaveScrollbars() const {
-    return HorizontalScrollbarMode() != kScrollbarAlwaysOff ||
-           VerticalScrollbarMode() != kScrollbarAlwaysOff;
-  }
-
   // The visible content rect has a location that is the scrolled offset of
   // the document. The width and height are the layout viewport width and
   // height. By default the scrollbars themselves are excluded from this
   // rectangle, but an optional boolean argument allows them to be included.
   IntRect VisibleContentRect(
       IncludeScrollbarsInRect = kExcludeScrollbars) const override;
   IntSize VisibleContentSize(
       IncludeScrollbarsInRect = kExcludeScrollbars) const;
 
   // Clips the provided rect to the visible content area. For this purpose, we
@@ skipping 367 matching lines @@
   void Init();
 
   void ClearLayoutSubtreeRootsAndMarkContainingBlocks();
 
   // Called when our frame rect changes (or the rect/scroll offset of an
   // ancestor changes).
   void FrameRectsChanged() override;
 
   bool ContentsInCompositedLayer() const;
 
-  void CalculateScrollbarModesFromOverflowStyle(const ComputedStyle*,
-                                                ScrollbarMode& h_mode,
-                                                ScrollbarMode& v_mode) const;
-
   void UpdateCounters();
   void ForceLayoutParentViewIfNeeded();
   void PerformPreLayoutTasks();
   void PerformLayout(bool in_subtree_layout);
   void ScheduleOrPerformPostLayoutTasks();
   void PerformPostLayoutTasks();
 
   void RecordDeferredLoadingStats();
 
   DocumentLifecycle& Lifecycle() const;
@@ skipping 315 matching lines @@
                   frame_or_plugin.IsFrameView());
 DEFINE_TYPE_CASTS(FrameView,
                   ScrollableArea,
                   scrollableArea,
                   scrollableArea->IsFrameView(),
                   scrollableArea.IsFrameView());
 
 }  // namespace blink
 
 #endif  // FrameView_h