Add attributes field to JSArray's SparseMap

Reviewed by Sam Weinig.

This will be necessary to be able to support non- writable/configurable/enumerable
properties, and helpful for getters/setters.

Added a concept of being 'inSparseMode' - this indicates the array has a non-standard

* runtime/ArrayPrototype.cpp:
(JSC::arrayProtoFuncSort):
    - JSArray::sort methods not allowed on arrays that are 'inSparseMode'.
      (must fall back to generic sort alogrithm).
* runtime/JSArray.cpp:
(JSC::JSArray::finishCreation):
    - moved reportedMapCapacity into the SparseArrayValueMap object.
(JSC::SparseArrayValueMap::find):
(JSC::SparseArrayValueMap::put):
(JSC::SparseArrayValueMap::visitChildren):
    - Added.
(JSC::JSArray::getOwnPropertySlotByIndex):
(JSC::JSArray::getOwnPropertyDescriptor):
(JSC::JSArray::putSlowCase):
(JSC::JSArray::deletePropertyByIndex):
(JSC::JSArray::getOwnPropertyNames):
(JSC::JSArray::setLength):
(JSC::JSArray::pop):
(JSC::JSArray::visitChildren):
    - Updated for changes in SparseArrayValueMap.
(JSC::JSArray::sortNumeric):
(JSC::JSArray::sort):
(JSC::JSArray::compactForSorting):
    - Disallow on 'SparseMode' arrays.
* runtime/JSArray.h:
(JSC::SparseArrayEntry::SparseArrayEntry):
    - An entry in the sparse array - value (WriteBarrier) + attributes.
(JSC::SparseArrayValueMap::SparseArrayValueMap):
(JSC::SparseArrayValueMap::sparseMode):
(JSC::SparseArrayValueMap::setSparseMode):
    - Flags to track whether an Array is forced into SparseMode.
(JSC::SparseArrayValueMap::remove):
(JSC::SparseArrayValueMap::notFound):
(JSC::SparseArrayValueMap::isEmpty):
(JSC::SparseArrayValueMap::contains):
(JSC::SparseArrayValueMap::size):
(JSC::SparseArrayValueMap::begin):
(JSC::SparseArrayValueMap::end):
    - accessors to the map
(JSC::SparseArrayValueMap::take):
    - only for use on non-SpareMode arrays.
(JSC::JSArray::inSparseMode):
    - Added.



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@103598 268f45cc-cd09-0410-ab3c-d52691b4dbfc