Binding generator should support key value iterable

Binding generator should support key value iterable
https://bugs.webkit.org/show_bug.cgi?id=154413

Reviewed by Darin Adler.

LayoutTests/imported/w3c:

* web-platform-tests/fetch/api/headers/headers-basic-expected.txt:
* web-platform-tests/fetch/api/headers/headers-basic.html:

Source/WebCore:

Covered by added layout and binding tests.

iterable<key, value> in a IDL file will trigger the generation of entries, keys, values, [Symbol.iterator] and forEach methods to the prototype.
Updated FetchHeaders and FontFaceSet to use it.

IDLParser.pm parses the iterable<> and adds an iterable field in the interface containing the iterable information and objects for the five operations.
IDLParser.pm is cleaned up a bit to remove previous Iterator support, which does not seem to be supported.

CodeGeneratorJS.pm is updated to generate the code for the five operations, using JSKeyValueIterator. Set iterators are not yet supported.
Moved definition of Iterator Key and Value Type to binding generated JSXX class based on iterable<> declaration in the IDL.

Added binding test and Fetch Headers tests.

* CMakeLists.txt:
* Modules/fetch/FetchHeaders.idl:
* WebCore.xcodeproj/project.pbxproj:
* bindings/js/JSBindingsAllInOne.cpp:
* bindings/js/JSFetchHeadersCustom.cpp: Removed.
* bindings/js/JSFontFaceSetCustom.cpp:
(WebCore::JSFontFaceSet::ready): Removed iterable custom methods.
* bindings/js/JSKeyValueIterator.h:
(WebCore::createKeyValueIterator):
(WebCore::keyValueIteratorForEach):
* bindings/scripts/CodeGeneratorJS.pm:
(GetFunctionName):
(PrototypeFunctionCount):
(PrototypePropertyCount):
(GeneratePropertiesHashTable):
(GenerateImplementation):
(GenerateImplementationFunctionCall):
(GenerateImplementationIterableFunctions):
* bindings/scripts/IDLParser.pm:
(parseOperationOrIterator):
(parseOperationOrIteratorRest):
(parseIterableRest):
(parseOptionalIterableInterface):
(applyMemberList):
(parseSpecial): Deleted.
* bindings/scripts/test/JS/JSTestObj.cpp:
(WebCore::JSTestObjPrototype::finishCreation):
(WebCore::jsTestObjPrototypeFunctionSymbolIterator):
(WebCore::jsTestObjPrototypeFunctionEntries):
(WebCore::jsTestObjPrototypeFunctionKeys):
(WebCore::jsTestObjPrototypeFunctionValues):
(WebCore::jsTestObjPrototypeFunctionForEach):
* bindings/scripts/test/TestObj.idl:
* css/FontFaceSet.idl:

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@196900 268f45cc-cd09-0410-ab3c-d52691b4dbfc