DevTools: [CSS] use setStyleText as undo action for setPropertyText

Source/core/inspector/InspectorCSSAgent.cpp

Index: Source/core/inspector/InspectorCSSAgent.cpp
diff --git a/Source/core/inspector/InspectorCSSAgent.cpp b/Source/core/inspector/InspectorCSSAgent.cpp
index 69aa4364f9ac238456ecb0d9888b54f6db2bf304..73eef80389b9e5eea94c37784be7685338962a82 100644
--- a/Source/core/inspector/InspectorCSSAgent.cpp
+++ b/Source/core/inspector/InspectorCSSAgent.cpp
@@ -229,7 +229,7 @@ public:
 
     virtual String toString() OVERRIDE
     {
-        return mergeId() + ": " + m_oldText + " -> " + m_text;
+        return mergeId() + ": " + m_oldStyleText + " -> " + m_text;
     }
 
     virtual bool perform(ExceptionState& exceptionState) OVERRIDE
@@ -240,14 +240,14 @@ public:
     virtual bool undo(ExceptionState& exceptionState) OVERRIDE
     {
         String placeholder;
-        return m_styleSheet->setPropertyText(m_cssId, m_propertyIndex, m_overwrite ? m_oldText : "", true, &placeholder, exceptionState);
+        return m_styleSheet->setStyleText(m_cssId, m_oldStyleText);
     }
 
     virtual bool redo(ExceptionState& exceptionState) OVERRIDE
     {
-        String oldText;
-        bool result = m_styleSheet->setPropertyText(m_cssId, m_propertyIndex, m_text, m_overwrite, &oldText, exceptionState);
-        m_oldText = oldText.stripWhiteSpace();
+        if (!m_styleSheet->getStyleText(m_cssId, &m_oldStyleText))
+            return false;
+        bool result = m_styleSheet->setPropertyText(m_cssId, m_propertyIndex, m_text, m_overwrite, exceptionState);
         return result;
     }
 
@@ -269,7 +269,7 @@ private:
     InspectorCSSId m_cssId;
     unsigned m_propertyIndex;
     String m_text;
-    String m_oldText;
+    String m_oldStyleText;
     bool m_overwrite;
 };