Fix compilation with clang

src/scanner-character-streams.cc

Index: src/scanner-character-streams.cc
diff --git a/src/scanner-character-streams.cc b/src/scanner-character-streams.cc
index fb503459f7f4cdb756e11773b739c84585c4f5d0..cbef3f95bb7086b4d411c8f5dc08c98f730153db 100644
--- a/src/scanner-character-streams.cc
+++ b/src/scanner-character-streams.cc
@@ -213,11 +213,11 @@ unsigned Utf8ToUtf16CharacterStream::FillBuffer(unsigned char_position,
 
 
 static const byte kUtf8MultiByteMask = 0xC0;
-static const byte kUtf8MultiByteCharStart = 0xC0;
 static const byte kUtf8MultiByteCharFollower = 0x80;
 
 
 #ifdef DEBUG
+static const byte kUtf8MultiByteCharStart = 0xC0;
 static bool IsUtf8MultiCharacterStart(byte first_byte) {
   return (first_byte & kUtf8MultiByteMask) == kUtf8MultiByteCharStart;
 }