Recalc styles on resize if we have viewport units.

Source/WebCore/css/StyleSheetContents.h

Index: Source/WebCore/css/StyleSheetContents.h
diff --git a/Source/WebCore/css/StyleSheetContents.h b/Source/WebCore/css/StyleSheetContents.h
index 40e2df3a937cf7fca45afeb110ae769bb8a438d3..e59546497e6648c1f9de5f43e311923fc00a4829 100644
--- a/Source/WebCore/css/StyleSheetContents.h
+++ b/Source/WebCore/css/StyleSheetContents.h
@@ -92,6 +92,7 @@ public:
     void parserAppendRule(PassRefPtr<StyleRuleBase>);
     void parserSetEncodingFromCharsetRule(const String& encoding); 
     void parserSetUsesRemUnits(bool b) { m_usesRemUnits = b; }
+    void parserSetUsesViewportUnits(bool b) { m_usesViewportUnits = b; }
 
     void clearRules();
 
@@ -117,6 +118,7 @@ public:
     StyleRuleBase* ruleAt(unsigned index) const;
 
     bool usesRemUnits() const { return m_usesRemUnits; }
+    bool usesViewportUnits() const { return m_usesViewportUnits; }
 
     unsigned estimatedSizeInBytes() const;
     
@@ -161,6 +163,7 @@ private:
     bool m_hasSyntacticallyValidCSSHeader : 1;
     bool m_didLoadErrorOccur : 1;
     bool m_usesRemUnits : 1;
+    bool m_usesViewportUnits : 1;
     bool m_isMutable : 1;
     bool m_isInMemoryCache : 1;