Move viewport unit resolution to style recalc time

Source/core/css/CSSToLengthConversionData.h

Index: Source/core/css/CSSToLengthConversionData.h
diff --git a/Source/core/css/CSSToLengthConversionData.h b/Source/core/css/CSSToLengthConversionData.h
index 975be5f212204717a2f5cbd80fc673695973677c..dffb91690ed90d23278e42dd8792c29cd4e491b1 100644
--- a/Source/core/css/CSSToLengthConversionData.h
+++ b/Source/core/css/CSSToLengthConversionData.h
@@ -37,21 +37,24 @@
 namespace WebCore {
 
 class RenderStyle;
+class RenderView;
 
 class CSSToLengthConversionData {
 public:
-    CSSToLengthConversionData(const RenderStyle* style, const RenderStyle* rootStyle, float zoom, bool computingFontSize = false)
+    CSSToLengthConversionData(const RenderStyle* style, const RenderStyle* rootStyle, const RenderView* renderView, float zoom, bool computingFontSize = false)
         : m_style(style)
         , m_rootStyle(rootStyle)
+        , m_renderView(renderView)
         , m_zoom(zoom)
         , m_useEffectiveZoom(false)
         , m_computingFontSize(computingFontSize)
     {
         ASSERT(zoom > 0);
     }
-    CSSToLengthConversionData(const RenderStyle* style, const RenderStyle* rootStyle, bool computingFontSize = false)
+    CSSToLengthConversionData(const RenderStyle* style, const RenderStyle* rootStyle, const RenderView* renderView, bool computingFontSize = false)
         : m_style(style)
         , m_rootStyle(rootStyle)
+        , m_renderView(renderView)
         , m_useEffectiveZoom(true)
         , m_computingFontSize(computingFontSize)
     {
@@ -61,17 +64,24 @@ public:
     float zoom() const;
     bool computingFontSize() const { return m_computingFontSize; }
 
+    // Accessing these marks the style as having viewport units

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

Do any other accessors mutate the object like this? Is there a cleaner
alternative?

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

I could move marking the style out into the conversion code that uses these in
CSSPrimitiveValue::computeLengthDouble. It would probably end up with a function
here markStyleAsHavingViewportUnits (since I'd rather this class stop returning
styles and just return pixel values for ems/exs/rems), and then this wouldn't be
a whole lot different to what's going on now?

+    double viewportWidthPercent() const;
+    double viewportHeightPercent() const;
+    double viewportMinPercent() const;
+    double viewportMaxPercent() const;
+
     void setStyle(const RenderStyle* style) { m_style = style; }
     void setRootStyle(const RenderStyle* rootStyle) { m_rootStyle = rootStyle; }
 
     CSSToLengthConversionData copyWithAdjustedZoom(float newZoom) const
     {
-        return CSSToLengthConversionData(m_style, m_rootStyle, newZoom, m_computingFontSize);
+        return CSSToLengthConversionData(m_style, m_rootStyle, m_renderView, newZoom, m_computingFontSize);
     }
 
 private:
     const RenderStyle* m_style;
     const RenderStyle* m_rootStyle;
+    const RenderView* m_renderView;
     float m_zoom;
     bool m_useEffectiveZoom;
     bool m_computingFontSize;