Unify JSC::IdentifierTable and WebCore::AtomicStringTable implementations.

Reviewed by Geoff Garen.

These two classes both implement a HashSet of uniqued StringImpls, with
translator classes to avoid unnecessary object creation. The only difference
between the classes is which flag (isIdentifier or inTable) is set.
Combine the two classes using a template predicated on which flag to use.

New class AtomicStringTable created, containing all the goodness from
IdentifierTable & AtomicStringTable, expect for Identifier's literalTable,
which has been moved onto JSGlobalData. Removed duplicate string translator
classes. Renamed StringImpl's inTable flag to more explicit 'isAtomic',
and set this on the empty string (which matches Identifier behaviour, and
removes a redundant check for zero-length).

* GNUmakefile.am:
* JavaScriptCore.gypi:
* JavaScriptCore.vcproj/WTF/WTF.vcproj:
* JavaScriptCore.xcodeproj/project.pbxproj:
* runtime/Identifier.cpp:
(JSC::createLiteralTable):
(JSC::deleteLiteralTable):
(JSC::Identifier::add):
(JSC::Identifier::addSlowCase):
* runtime/Identifier.h:
* runtime/JSGlobalData.cpp:
(JSC::JSGlobalData::JSGlobalData):
(JSC::JSGlobalData::~JSGlobalData):
* runtime/JSGlobalData.h:
* wtf/WTFThreadData.cpp:
(WTF::WTFThreadData::WTFThreadData):
(WTF::WTFThreadData::~WTFThreadData):
* wtf/WTFThreadData.h:
(WTF::WTFThreadData::atomicStringTable):
* wtf/text/AtomicString.cpp:
(WebCore::table):
(WebCore::operator==):
(WebCore::AtomicString::add):
(WebCore::AtomicString::find):
(WebCore::AtomicString::remove):
* wtf/text/AtomicStringTable.h: Added.
(WTF::CStringTranslator::hash):
(WTF::CStringTranslator::equal):
(WTF::CStringTranslator::translate):
(WTF::UCharBufferTranslator::hash):
(WTF::UCharBufferTranslator::equal):
(WTF::UCharBufferTranslator::translate):
(WTF::HashAndCharactersTranslator::hash):
(WTF::HashAndCharactersTranslator::equal):
(WTF::HashAndCharactersTranslator::translate):
(WTF::IdentifierOrAtomicStringTable::remove):
(WTF::::~IdentifierOrAtomicStringTable):
(WTF::::add):
(WTF::::find):
* wtf/text/StringImpl.cpp:
(WebCore::StringImpl::~StringImpl):
* wtf/text/StringImpl.h:
(WebCore::StringImpl::isAtomic):
(WebCore::StringImpl::setIsAtomic):
(WebCore::equal):
* wtf/text/StringImplBase.h:
(WTF::StringImplBase::StringImplBase):



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@58114 268f45cc-cd09-0410-ab3c-d52691b4dbfc