Use StringBuilder::appendLiteral() / StringBuilder::append(char) when possible

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 edb9a8d8bee71a929bca2cb0653d42c044e99915..dff022bae5673f6f95da436e173e6fc05ed55352 100644
--- a/Source/modules/websockets/WebSocketHandshake.cpp
+++ b/Source/modules/websockets/WebSocketHandshake.cpp
@@ -174,8 +174,11 @@ String WebSocketHandshake::clientOrigin() const
 String WebSocketHandshake::clientLocation() const
 {
     StringBuilder builder;
-    builder.append(m_secure ? "wss" : "ws");
-    builder.append("://");
+    if (m_secure)
+        builder.appendLiteral("wss");
+    else
+        builder.appendLiteral("ws");
+    builder.appendLiteral("://");
     builder.append(hostName(m_url, m_secure));
     builder.append(resourceName(m_url));
     return builder.toString();
@@ -188,9 +191,9 @@ CString WebSocketHandshake::clientHandshakeMessage() const
     // Keep the following consistent with clientHandshakeRequest().
     StringBuilder builder;
 
-    builder.append("GET ");
+    builder.appendLiteral("GET ");
     builder.append(resourceName(m_url));
-    builder.append(" HTTP/1.1\r\n");
+    builder.appendLiteral(" HTTP/1.1\r\n");
 
     Vector<String> fields;
     fields.append("Upgrade: websocket");
@@ -221,10 +224,10 @@ CString WebSocketHandshake::clientHandshakeMessage() const
 
     for (size_t i = 0; i < fields.size(); i++) {
         builder.append(fields[i]);
-        builder.append("\r\n");
+        builder.appendLiteral("\r\n");
     }
 
-    builder.append("\r\n");
+    builder.appendLiteral("\r\n");
 
     return builder.toString().utf8();
 }