[ES6] Enable ES6 Modules

[ES6] Enable ES6 Modules
https://bugs.webkit.org/show_bug.cgi?id=165849

Reviewed by Geoffrey Garen.

Source/JavaScriptCore:

* features.json:

Source/WebCore:

* dom/ScriptElement.cpp:
(WebCore::ScriptElement::determineScriptType):
* html/parser/HTMLPreloadScanner.cpp:
(WebCore::TokenPreloadScanner::StartTagScanner::processAttribute):
* page/Settings.in:

Source/WebKit/mac:

* WebView/WebPreferenceKeysPrivate.h:
* WebView/WebPreferences.mm:
(+[WebPreferences initialize]):
(-[WebPreferences es6ModulesEnabled]): Deleted.
(-[WebPreferences setES6ModulesEnabled:]): Deleted.
* WebView/WebPreferencesPrivate.h:
* WebView/WebView.mm:
(-[WebView _preferencesChanged:]):

Source/WebKit/win:

* Interfaces/IWebPreferencesPrivate.idl:
* WebPreferenceKeysPrivate.h:
* WebPreferences.cpp:
(WebPreferences::setES6ModulesEnabled): Deleted.
(WebPreferences::es6ModulesEnabled): Deleted.
* WebPreferences.h:
* WebView.cpp:
(WebView::notifyPreferencesChanged):

Source/WebKit2:

* Shared/WebPreferencesDefinitions.h:
* UIProcess/API/C/WKPreferences.cpp:
(WKPreferencesSetES6ModulesEnabled): Deleted.
(WKPreferencesGetES6ModulesEnabled): Deleted.
* UIProcess/API/C/WKPreferencesRefPrivate.h:
* WebProcess/InjectedBundle/InjectedBundle.cpp:
(WebKit::InjectedBundle::overrideBoolPreferenceForTestRunner):
* WebProcess/WebPage/WebPage.cpp:
(WebKit::WebPage::updatePreferences):

Tools:

* DumpRenderTree/mac/DumpRenderTree.mm:
(resetWebPreferencesToConsistentValues):
* DumpRenderTree/win/DumpRenderTree.cpp:
(resetWebPreferencesToConsistentValues):
* WebKitTestRunner/InjectedBundle/InjectedBundle.cpp:
(WTR::InjectedBundle::beginTesting):
* WebKitTestRunner/InjectedBundle/TestRunner.cpp:
(WTR::TestRunner::setES6ModulesEnabled): Deleted.
* WebKitTestRunner/InjectedBundle/TestRunner.h:

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@210016 268f45cc-cd09-0410-ab3c-d52691b4dbfc