Revert of Remove StringBuilder::appendLiteral.

third_party/WebKit/Source/core/page/EventSource.cpp

Index: third_party/WebKit/Source/core/page/EventSource.cpp
diff --git a/third_party/WebKit/Source/core/page/EventSource.cpp b/third_party/WebKit/Source/core/page/EventSource.cpp
index dfa1f8289d154986d315a5abf99f78602dc7ea0c..1c6b1be6a8902772c484152ebf8fae4ab29a781c 100644
--- a/third_party/WebKit/Source/core/page/EventSource.cpp
+++ b/third_party/WebKit/Source/core/page/EventSource.cpp
@@ -238,9 +238,9 @@
         responseIsValid = charset.isEmpty() || equalIgnoringCase(charset, "UTF-8");
         if (!responseIsValid) {
             StringBuilder message;
-            message.append("EventSource's response has a charset (\"");
+            message.appendLiteral("EventSource's response has a charset (\"");
             message.append(charset);
-            message.append("\") that is not UTF-8. Aborting the connection.");
+            message.appendLiteral("\") that is not UTF-8. Aborting the connection.");
             // FIXME: We are missing the source line.
             getExecutionContext()->addConsoleMessage(ConsoleMessage::create(JSMessageSource, ErrorMessageLevel, message.toString()));
         }
@@ -248,9 +248,9 @@
         // To keep the signal-to-noise ratio low, we only log 200-response with an invalid MIME type.
         if (statusCode == 200 && !mimeTypeIsValid) {
             StringBuilder message;
-            message.append("EventSource's response has a MIME type (\"");
+            message.appendLiteral("EventSource's response has a MIME type (\"");
             message.append(response.mimeType());
-            message.append("\") that is not \"text/event-stream\". Aborting the connection.");
+            message.appendLiteral("\") that is not \"text/event-stream\". Aborting the connection.");
             // FIXME: We are missing the source line.
             getExecutionContext()->addConsoleMessage(ConsoleMessage::create(JSMessageSource, ErrorMessageLevel, message.toString()));
         }