Move viewport unit resolution to style recalc time

Source/core/rendering/RenderScrollbarPart.cpp

Index: Source/core/rendering/RenderScrollbarPart.cpp
diff --git a/Source/core/rendering/RenderScrollbarPart.cpp b/Source/core/rendering/RenderScrollbarPart.cpp
index 13a35ebb8326d035ebb446f04408da66e19059ee..8df91634ba507729f9aac25c3c407deca4f34bb5 100644
--- a/Source/core/rendering/RenderScrollbarPart.cpp
+++ b/Source/core/rendering/RenderScrollbarPart.cpp
@@ -88,10 +88,10 @@ void RenderScrollbarPart::layoutVerticalPart()
     }
 }
 
-static int calcScrollbarThicknessUsing(SizeType sizeType, const Length& length, int containingLength, RenderView* renderView)
+static int calcScrollbarThicknessUsing(SizeType sizeType, const Length& length, int containingLength)
 {
     if (!length.isIntrinsicOrAuto() || (sizeType == MinSize && length.isAuto()))
-        return minimumValueForLength(length, containingLength, renderView);
+        return minimumValueForLength(length, containingLength);
     return ScrollbarTheme::theme()->scrollbarThickness();
 }
 
@@ -99,36 +99,34 @@ void RenderScrollbarPart::computeScrollbarWidth()
 {
     if (!m_scrollbar->owningRenderer())
         return;
-    RenderView* renderView = view();
     // FIXME: We are querying layout information but nothing guarantees that it's up-to-date, especially since we are called at style change.
     // FIXME: Querying the style's border information doesn't work on table cells with collapsing borders.
     int visibleSize = m_scrollbar->owningRenderer()->width() - m_scrollbar->owningRenderer()->style()->borderLeftWidth() - m_scrollbar->owningRenderer()->style()->borderRightWidth();
-    int w = calcScrollbarThicknessUsing(MainOrPreferredSize, style()->width(), visibleSize, renderView);
-    int minWidth = calcScrollbarThicknessUsing(MinSize, style()->minWidth(), visibleSize, renderView);
-    int maxWidth = style()->maxWidth().isUndefined() ? w : calcScrollbarThicknessUsing(MaxSize, style()->maxWidth(), visibleSize, renderView);
+    int w = calcScrollbarThicknessUsing(MainOrPreferredSize, style()->width(), visibleSize);
+    int minWidth = calcScrollbarThicknessUsing(MinSize, style()->minWidth(), visibleSize);
+    int maxWidth = style()->maxWidth().isUndefined() ? w : calcScrollbarThicknessUsing(MaxSize, style()->maxWidth(), visibleSize);
     setWidth(max(minWidth, min(maxWidth, w)));
 
     // Buttons and track pieces can all have margins along the axis of the scrollbar.
-    m_marginBox.setLeft(minimumValueForLength(style()->marginLeft(), visibleSize, renderView));
-    m_marginBox.setRight(minimumValueForLength(style()->marginRight(), visibleSize, renderView));
+    m_marginBox.setLeft(minimumValueForLength(style()->marginLeft(), visibleSize));
+    m_marginBox.setRight(minimumValueForLength(style()->marginRight(), visibleSize));
 }
 
 void RenderScrollbarPart::computeScrollbarHeight()
 {
     if (!m_scrollbar->owningRenderer())
         return;
-    RenderView* renderView = view();
     // FIXME: We are querying layout information but nothing guarantees that it's up-to-date, especially since we are called at style change.
     // FIXME: Querying the style's border information doesn't work on table cells with collapsing borders.
     int visibleSize = m_scrollbar->owningRenderer()->height() -  m_scrollbar->owningRenderer()->style()->borderTopWidth() - m_scrollbar->owningRenderer()->style()->borderBottomWidth();
-    int h = calcScrollbarThicknessUsing(MainOrPreferredSize, style()->height(), visibleSize, renderView);
-    int minHeight = calcScrollbarThicknessUsing(MinSize, style()->minHeight(), visibleSize, renderView);
-    int maxHeight = style()->maxHeight().isUndefined() ? h : calcScrollbarThicknessUsing(MaxSize, style()->maxHeight(), visibleSize, renderView);
+    int h = calcScrollbarThicknessUsing(MainOrPreferredSize, style()->height(), visibleSize);
+    int minHeight = calcScrollbarThicknessUsing(MinSize, style()->minHeight(), visibleSize);
+    int maxHeight = style()->maxHeight().isUndefined() ? h : calcScrollbarThicknessUsing(MaxSize, style()->maxHeight(), visibleSize);
     setHeight(max(minHeight, min(maxHeight, h)));
 
     // Buttons and track pieces can all have margins along the axis of the scrollbar.
-    m_marginBox.setTop(minimumValueForLength(style()->marginTop(), visibleSize, renderView));
-    m_marginBox.setBottom(minimumValueForLength(style()->marginBottom(), visibleSize, renderView));
+    m_marginBox.setTop(minimumValueForLength(style()->marginTop(), visibleSize));
+    m_marginBox.setBottom(minimumValueForLength(style()->marginBottom(), visibleSize));
 }
 
 void RenderScrollbarPart::computePreferredLogicalWidths()