Add a WebDocument::watchCssSelectors(selectors)

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 cf5a7f5dc1eb1707146c589d267bb8c7a21e182d..9057037b0a193b6c62783f4e47694743f582b10f 100644
--- a/Source/core/css/resolver/StyleResolverState.cpp
+++ b/Source/core/css/resolver/StyleResolverState.cpp
@@ -45,6 +45,7 @@ void StyleResolverState::cacheBorderAndBackground()
 void StyleResolverState::clear()
 {
     m_element = 0;
+    m_style = 0;
     m_styledElement = 0;
     m_parentStyle = 0;
     m_parentNode = 0;
@@ -52,6 +53,13 @@ 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)