Add runtime and compile time flags for enabling Web Animations API and model.

Add runtime and compile time flags for enabling Web Animations API and model.
https://bugs.webkit.org/show_bug.cgi?id=150914

Patch by Nikos Andronikos <nikos.andronikos-webkit@cisra.canon.com.au> on 2015-11-05
Reviewed by Benjamin Poulain.

Add ENABLE_WEB_ANIMATIONS compile time flag, runtime flag webAnimationsEnabled and Expose WK2 preference for runtime flag.

.:

* Source/cmake/OptionsWin.cmake:
* Source/cmake/WebKitFeatures.cmake:

Source/JavaScriptCore:

* Configurations/FeatureDefines.xcconfig:

Source/WebCore:

* Configurations/FeatureDefines.xcconfig:
* bindings/generic/RuntimeEnabledFeatures.cpp:
(WebCore::RuntimeEnabledFeatures::RuntimeEnabledFeatures):
* bindings/generic/RuntimeEnabledFeatures.h:
(WebCore::RuntimeEnabledFeatures::setWebAnimationsEnabled):
(WebCore::RuntimeEnabledFeatures::webAnimationsEnabled):

Source/WebKit/mac:

* Configurations/FeatureDefines.xcconfig:

Source/WebKit2:

* Configurations/FeatureDefines.xcconfig:
* Shared/WebPreferencesDefinitions.h:
* UIProcess/API/C/WKPreferences.cpp:
(WKPreferencesSetWebAnimationsEnabled):
(WKPreferencesGetWebAnimationsEnabled):
* UIProcess/API/C/WKPreferencesRefPrivate.h:
* WebProcess/InjectedBundle/InjectedBundle.cpp:
(WebKit::InjectedBundle::overrideBoolPreferenceForTestRunner):
(WebKit::InjectedBundle::setWebAnimationsEnabled):
* WebProcess/InjectedBundle/InjectedBundle.h:
* WebProcess/WebPage/WebPage.cpp:
(WebKit::WebPage::updatePreferences):

Source/WTF:

* wtf/FeatureDefines.h:

Tools:

* Scripts/webkitperl/FeatureList.pm:

WebKitLibraries:

* win/tools/vsprops/FeatureDefines.props:
* win/tools/vsprops/FeatureDefinesCairo.props:

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@192093 268f45cc-cd09-0410-ab3c-d52691b4dbfc