Move viewport unit resolution to style recalc time

Source/core/rendering/RenderView.cpp

Index: Source/core/rendering/RenderView.cpp
diff --git a/Source/core/rendering/RenderView.cpp b/Source/core/rendering/RenderView.cpp
index 05955691af573fc99f2d0102d0b46c6a62b72e2f..4fa84d30c22c9a2e7dec036128aadb105bffbc63 100644
--- a/Source/core/rendering/RenderView.cpp
+++ b/Source/core/rendering/RenderView.cpp
@@ -320,10 +320,7 @@ void RenderView::layout()
             if ((child->isBox() && toRenderBox(child)->hasRelativeLogicalHeight())
                     || child->style()->logicalHeight().isPercent()
                     || child->style()->logicalMinHeight().isPercent()
-                    || child->style()->logicalMaxHeight().isPercent()
-                    || child->style()->logicalHeight().isViewportPercentage()
-                    || child->style()->logicalMinHeight().isViewportPercentage()
-                    || child->style()->logicalMaxHeight().isViewportPercentage())
+                    || child->style()->logicalMaxHeight().isPercent())
                 layoutScope.setChildNeedsLayout(child);
         }
 
@@ -1213,26 +1210,26 @@ bool RenderView::backgroundIsKnownToBeOpaqueInRect(const LayoutRect&) const
     return m_frameView->hasOpaqueBackground();
 }
 
-LayoutUnit RenderView::viewportPercentageWidth(float percentage) const
+double RenderView::viewportWidthPercent() const

[johnme, 2013/12/18 12:04:15]

1. This doesn't seem to return a percentage?

2. Is this the initial viewport (window width in DIPs, affected only by page
zoom), layout viewport (also affected by @viewport and meta viewport) or actual
viewport (also affected by pinch zoom)? Since viewWidth uses
FrameView::layoutSize, which is set by WebViewImpl::setFixedLayoutSize, it seems
that this is probably the layout viewport size.

Consider renaming this to layoutViewportWidth (similarly below, and in
CSSToLengthConversionData).

[Timothy Loh, 2013/12/23 06:28:16]

See comment (message) above.

 {
-    return viewLogicalWidth(ScrollableArea::IncludeScrollbars) * percentage / 100.f;
+    float scale = m_frameView ? m_frameView->frame().pageZoomFactor() : 1;
+    return viewWidth(ScrollableArea::IncludeScrollbars) / scale / 100.f;

[johnme, 2013/12/18 12:04:15]

According to http://www.w3.org/TR/css3-values/#viewport-relative-lengths, vw et
al are relative to the size of the initial containing block, whose "size is
affected by the presence of scrollbars on the viewport". Since the size depends
on the presence of scrollbars, shouldn't this be using ExcludeScrollbars
instead?

[Timothy Loh, 2013/12/23 06:28:16]

Possibly; but that would have to be a separate patch (I'm just trying to move
resolution to style time in this patch).

 }
 
-LayoutUnit RenderView::viewportPercentageHeight(float percentage) const
+double RenderView::viewportHeightPercent() const
 {
-    return viewLogicalHeight(ScrollableArea::IncludeScrollbars) * percentage / 100.f;
+    float scale = m_frameView ? m_frameView->frame().pageZoomFactor() : 1;
+    return viewHeight(ScrollableArea::IncludeScrollbars) / scale / 100.f;
 }
 
-LayoutUnit RenderView::viewportPercentageMin(float percentage) const
+double RenderView::viewportMinPercent() const
 {
-    return std::min(viewLogicalWidth(ScrollableArea::IncludeScrollbars), viewLogicalHeight(ScrollableArea::IncludeScrollbars))
-        * percentage / 100.f;
+    return std::min(viewportWidthPercent(), viewportHeightPercent());
 }
 
-LayoutUnit RenderView::viewportPercentageMax(float percentage) const
+double RenderView::viewportMaxPercent() const
 {
-    return std::max(viewLogicalWidth(ScrollableArea::IncludeScrollbars), viewLogicalHeight(ScrollableArea::IncludeScrollbars))
-        * percentage / 100.f;
+    return std::max(viewportWidthPercent(), viewportHeightPercent());
 }
 
 FragmentationDisabler::FragmentationDisabler(RenderObject* root)