Switch remaining cases of string construction to use StringBuilder.
Builds strings using a vector rather than using string append / addition.

Reviewed by Sam Weinig.

* JavaScriptCore.exp:
* JavaScriptCore.xcodeproj/project.pbxproj:
* runtime/Executable.cpp:
(JSC::FunctionExecutable::paramString):
* runtime/FunctionConstructor.cpp:
(JSC::constructFunction):
* runtime/JSGlobalObjectFunctions.cpp:
(JSC::encode):
(JSC::decode):
(JSC::globalFuncEscape):
(JSC::globalFuncUnescape):
* runtime/JSONObject.cpp:
(JSC::Stringifier::stringify):
(JSC::Stringifier::indent):
* runtime/JSString.h:
* runtime/LiteralParser.cpp:
(JSC::LiteralParser::Lexer::lexString):
* runtime/NumberPrototype.cpp:
(JSC::integerPartNoExp):
(JSC::numberProtoFuncToFixed):
(JSC::numberProtoFuncToPrecision):
* runtime/Operations.h:
(JSC::jsString):
* runtime/StringPrototype.cpp:
(JSC::substituteBackreferencesSlow):
(JSC::substituteBackreferences):
(JSC::stringProtoFuncConcat):



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@52075 268f45cc-cd09-0410-ab3c-d52691b4dbfc