Removed 'String::append' from some of the blink source.

Source/modules/websockets/WebSocketHandshake.cpp

Index: Source/modules/websockets/WebSocketHandshake.cpp
diff --git a/Source/modules/websockets/WebSocketHandshake.cpp b/Source/modules/websockets/WebSocketHandshake.cpp
index b0ed328eb15260c46a096eeea958649db3264814..e5e728fcfeb9b3abed681026a3b762206b22c466 100644
--- a/Source/modules/websockets/WebSocketHandshake.cpp
+++ b/Source/modules/websockets/WebSocketHandshake.cpp
@@ -104,10 +104,9 @@ static String hostName(const KURL& url, bool secure)
 static const size_t maxInputSampleSize = 128;
 static String trimInputSample(const char* p, size_t len)
 {
-    String s = String(p, std::min<size_t>(len, maxInputSampleSize));
     if (len > maxInputSampleSize)
-        s.append(horizontalEllipsis);
-    return s;
+        return String(p, maxInputSampleSize) + horizontalEllipsis;
+    return String(p, len);
 }
 
 static String generateSecWebSocketKey()