Add a CustomSchemeHandler runtime flag to remove ENABLE(CUSTOM_SCHEME_HANDLER)

Source/modules/navigatorcontentutils/NavigatorContentUtils.cpp

 /*
  * Copyright (C) 2011, Google Inc. All rights reserved.
  * Copyright (C) 2012, Samsung Electronics. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 136 matching lines @@
 
     if (!verifyCustomHandlerURL(baseURL, url, exceptionState))
         return;
 
     if (!verifyProtocolHandlerScheme(scheme, "registerProtocolHandler", exceptionState))
         return;
 
     NavigatorContentUtils::from(navigator->frame()->page())->client()->registerProtocolHandler(scheme, baseURL, url, title);
 }
 
-#if ENABLE(CUSTOM_SCHEME_HANDLER)
 static String customHandlersStateString(const NavigatorContentUtilsClient::CustomHandlersState state)
 {
     DEFINE_STATIC_LOCAL(const String, newHandler, ("new"));
     DEFINE_STATIC_LOCAL(const String, registeredHandler, ("registered"));
     DEFINE_STATIC_LOCAL(const String, declinedHandler, ("declined"));
 
     switch (state) {
     case NavigatorContentUtilsClient::CustomHandlersNew:
         return newHandler;
     case NavigatorContentUtilsClient::CustomHandlersRegistered:
@@ skipping 34 matching lines @@
     String baseURL = document->baseURL().baseAsString();
 
     if (!verifyCustomHandlerURL(baseURL, url, exceptionState))
         return;
 
     if (!verifyProtocolHandlerScheme(scheme, "unregisterProtocolHandler", exceptionState))
         return;
 
     NavigatorContentUtils::from(navigator->frame()->page())->client()->unregisterProtocolHandler(scheme, baseURL, url);
 }
-#endif
 
 const char* NavigatorContentUtils::supplementName()
 {
     return "NavigatorContentUtils";
 }
 
 void provideNavigatorContentUtilsTo(Page* page, NavigatorContentUtilsClient* client)
 {
     RefCountedSupplement<Page, NavigatorContentUtils>::provideTo(page, NavigatorContentUtils::supplementName(), NavigatorContentUtils::create(client));
 }
 
 } // namespace WebCore