Encoding API: Update tests and simplify constructors

Source/modules/encoding/TextEncoder.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 37 matching lines @@
         exceptionState.throwTypeError("The encoding label provided ('" + encodingLabel + "') is invalid.");
         return 0;
     }
 
     String name(encoding.name());
     if (name != "UTF-8" && name != "UTF-16LE" && name != "UTF-16BE") {
         exceptionState.throwTypeError("The encoding provided ('" + encodingLabel + "') is not one of 'utf-8', 'utf-16', or 'utf-16be'.");
         return 0;
     }
 
-    return new TextEncoder(encoding.name());
+    return new TextEncoder(encoding);
 }
 
-TextEncoder::TextEncoder(const String& encoding)
+TextEncoder::TextEncoder(const WTF::TextEncoding& encoding)
     : m_encoding(encoding)
-    , m_codec(newTextCodec(m_encoding))
+    , m_codec(newTextCodec(encoding))
 {
 }
 
 TextEncoder::~TextEncoder()
 {
 }
 
 String TextEncoder::encoding() const
 {
     String name = String(m_encoding.name()).lower();
@@ skipping 15 matching lines @@
     else
         result = m_codec->encode(input.characters16(), input.length(), WTF::QuestionMarksForUnencodables);
 
     const char* buffer = result.data();
     const unsigned char* unsignedBuffer = reinterpret_cast<const unsigned char*>(buffer);
 
     return Uint8Array::create(unsignedBuffer, result.length());
 }
 
 } // namespace WebCore