Remove ThemeColor runtime feature

Source/core/html/HTMLMetaElement-in.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2003, 2010 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 454 matching lines @@
     const AtomicString& nameValue = fastGetAttribute(nameAttr);
     if (!nameValue.isEmpty()) {
         if (equalIgnoringCase(nameValue, "viewport"))
             processViewportContentAttribute(contentValue, ViewportDescription::ViewportMeta);
         else if (equalIgnoringCase(nameValue, "referrer"))
             document().processReferrerPolicy(contentValue);
         else if (equalIgnoringCase(nameValue, "handheldfriendly") && equalIgnoringCase(contentValue, "true"))
             processViewportContentAttribute("width=device-width", ViewportDescription::HandheldFriendlyMeta);
         else if (equalIgnoringCase(nameValue, "mobileoptimized"))
             processViewportContentAttribute("width=device-width, initial-scale=1", ViewportDescription::MobileOptimizedMeta);
-        else if (RuntimeEnabledFeatures::themeColorEnabled() && equalIgnoringCase(nameValue, "theme-color") && document().frame())
+        else if (equalIgnoringCase(nameValue, "theme-color") && document().frame())
             document().frame()->loader().client()->dispatchDidChangeThemeColor();
     }
 
     // Get the document to process the tag, but only if we're actually part of DOM
     // tree (changing a meta tag while it's not in the tree shouldn't have any effect
     // on the document).
 
     const AtomicString& httpEquivValue = fastGetAttribute(http_equivAttr);
     if (!httpEquivValue.isEmpty())
         document().processHttpEquiv(httpEquivValue, contentValue, inDocumentHead(this));
 }
 
 const AtomicString& HTMLMetaElement::content() const
 {
     return getAttribute(contentAttr);
 }
 
 const AtomicString& HTMLMetaElement::httpEquiv() const
 {
     return getAttribute(http_equivAttr);
 }
 
 const AtomicString& HTMLMetaElement::name() const
 {
     return getNameAttribute();
 }
 
 }