fourthTier: String::utf8() should also be available as StringImpl::utf8() so that you don't have to ref() a StringImpl just to get its utf8()
https://bugs.webkit.org/show_bug.cgi?id=115393

Reviewed by Geoffrey Garen.

Source/JavaScriptCore:

* runtime/JSGlobalObjectFunctions.cpp:
(JSC::encode):

Source/WebCore:

No new tests because no new behavior.

* Modules/websockets/WebSocket.cpp:
(WebCore::WebSocket::close):
* Modules/websockets/WebSocketChannel.cpp:
(WebCore::WebSocketChannel::send):
* html/MediaFragmentURIParser.cpp:
(WebCore::MediaFragmentURIParser::parseFragments):

Source/WTF:

* WTF.xcodeproj/project.pbxproj:
* wtf/text/ConversionMode.h: Added.
(WTF):
* wtf/text/StringImpl.cpp:
(WTF):
(WTF::putUTF8Triple):
(WTF::StringImpl::utf8):
* wtf/text/StringImpl.h:
(StringImpl):
* wtf/text/WTFString.cpp:
(WTF):
(WTF::String::utf8):
* wtf/text/WTFString.h:
(String):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@153135 268f45cc-cd09-0410-ab3c-d52691b4dbfc