Implement unregisterProtocolHandler() function on CUSTOM_SCHEME_HANDLER

Source/web/WebRuntimeFeatures.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 369 matching lines @@
 void WebRuntimeFeatures::enableHTMLImports(bool enable)
 {
     RuntimeEnabledFeatures::setHTMLImportsEnabled(enable);
 }
 
 bool WebRuntimeFeatures::isHTMLImportsEnabled()
 {
     return RuntimeEnabledFeatures::htmlImportsEnabled();
 }
 
+void WebRuntimeFeatures::enableCustomSchemeHandler(bool enable)
+{
+#if ENABLE(CUSTOM_SCHEME_HANDLER)
+    RuntimeEnabledFeatures::setCustomSchemeHandlerEnabled(enable);
+#endif
+}
+
+bool WebRuntimeFeatures::isCustomSchemeHandlerEnabled()
+{
+#if ENABLE(CUSTOM_SCHEME_HANDLER)
+    return RuntimeEnabledFeatures::customSchemeHandlerEnabled();
+#else
+    return false;
+#endif
+}
+
 // FIXME: Remove this when embedders switch to enableEmbedderCustomElements.
 void WebRuntimeFeatures::enableCustomElements(bool enable)
 {
     RuntimeEnabledFeatures::setCustomElementsEnabled(enable);
     enableEmbedderCustomElements(enable);
 }
 
 void WebRuntimeFeatures::enableEmbedderCustomElements(bool enable)
 {
     RuntimeEnabledFeatures::setEmbedderCustomElementsEnabled(enable);
 }
 
 void WebRuntimeFeatures::enableOverlayScrollbars(bool enable)
 {
     RuntimeEnabledFeatures::setOverlayScrollbarsEnabled(enable);
 }
 
 } // namespace WebKit