Clear StyleResolverState after each resolve.

Source/core/css/resolver/StyleResolverState.cpp

Index: Source/core/css/resolver/StyleResolverState.cpp
diff --git a/Source/core/css/resolver/StyleResolverState.cpp b/Source/core/css/resolver/StyleResolverState.cpp
index 32d0fae7d390923816d43847d9fa6d0cea84c672..6d5755bd3e4688b225107b69dce40e193de84257 100644
--- a/Source/core/css/resolver/StyleResolverState.cpp
+++ b/Source/core/css/resolver/StyleResolverState.cpp
@@ -34,6 +34,7 @@ namespace WebCore {
 void StyleResolverState::clear()
 {
     m_element = 0;
+    m_style = 0;
     m_styledElement = 0;
     m_parentStyle = 0;
     m_parentNode = 0;
@@ -41,6 +42,13 @@ void StyleResolverState::clear()
     m_elementStyleResources.clear();
 }
 
+PassRefPtr<RenderStyle> StyleResolverState::takeStyleAndClear()
+{
+    RefPtr<RenderStyle> result = takeStyle();
+    clear();
+    return result.release();
+}
+
 void StyleResolverState::initElement(Element* element)
 {
     if (m_element == element)