Fixing inconsistency with Media Query append/deleteMedium.

Source/core/css/MediaList.h

Index: Source/core/css/MediaList.h
diff --git a/Source/core/css/MediaList.h b/Source/core/css/MediaList.h
index cc6903552ba272db8496fd6e6f191a9b6e56f5c5..a299ba097eabbecd0991a97ea14264d3f408db2d 100644
--- a/Source/core/css/MediaList.h
+++ b/Source/core/css/MediaList.h
@@ -52,7 +52,7 @@ public:
     }
     ~MediaQuerySet();
 
-    bool parse(const String&);
+    bool set(const String&);
     bool add(const String&);
     bool remove(const String&);
 
@@ -75,9 +75,10 @@ private:
     MediaQuerySet(const MediaQuerySet&);
 
     PassOwnPtr<MediaQuery> parseMediaQuery(const String&);
+    void parseMediaQueryList(const String&, Vector<OwnPtr<MediaQuery> >& result);
 
     unsigned m_fallbackToDescriptor : 1; // true if failed media query parsing should fallback to media description parsing.
-    signed m_lastLine : 31;
+    unsigned m_lastLine : 31;
     Vector<OwnPtr<MediaQuery> > m_queries;
 };
 
@@ -100,7 +101,7 @@ public:
     void appendMedium(const String& newMedium, ExceptionCode&);
 
     String mediaText() const { return m_mediaQueries->mediaText(); }
-    void setMediaText(const String&, ExceptionCode&);
+    void setMediaText(const String&);
 
     // Not part of CSSOM.
     CSSRule* parentRule() const { return m_parentRule; }