Allow Web Animations flags to be turned off as well as on

Source/web/WebRuntimeFeatures.cpp

Index: Source/web/WebRuntimeFeatures.cpp
diff --git a/Source/web/WebRuntimeFeatures.cpp b/Source/web/WebRuntimeFeatures.cpp
index 10f809c75d77b6757fafeba38a7fb68f34ef5217..ba7bf85ee4ba0cfa47389370266b11bcae84d6e0 100644
--- a/Source/web/WebRuntimeFeatures.cpp
+++ b/Source/web/WebRuntimeFeatures.cpp
@@ -349,16 +349,16 @@ bool WebRuntimeFeatures::isTouchEnabled()
     return RuntimeEnabledFeatures::touchEnabled();
 }
 
-void WebRuntimeFeatures::enableWebAnimationsCSS()
+void WebRuntimeFeatures::enableWebAnimationsCSS(bool enable)
 {
-    RuntimeEnabledFeatures::setWebAnimationsEnabled(true);
-    RuntimeEnabledFeatures::setWebAnimationsCSSEnabled(true);
+    RuntimeEnabledFeatures::setWebAnimationsEnabled(enable || RuntimeEnabledFeatures::webAnimationsSVGEnabled());
+    RuntimeEnabledFeatures::setWebAnimationsCSSEnabled(enable);
 }
 
-void WebRuntimeFeatures::enableWebAnimationsSVG()
+void WebRuntimeFeatures::enableWebAnimationsSVG(bool enable)
 {
-    RuntimeEnabledFeatures::setWebAnimationsEnabled(true);
-    RuntimeEnabledFeatures::setWebAnimationsSVGEnabled(true);
+    RuntimeEnabledFeatures::setWebAnimationsEnabled(enable || RuntimeEnabledFeatures::webAnimationsCSSEnabled());
+    RuntimeEnabledFeatures::setWebAnimationsSVGEnabled(enable);
 }
 
 void WebRuntimeFeatures::enableWebAudio(bool enable)