Make 'inputmode' attribute experimental from test.

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 261 matching lines @@
 void WebRuntimeFeatures::enableXSLT(bool enable)
 {
     RuntimeEnabledFeatures::setXSLTEnabled(enable);
 }
 
 void WebRuntimeFeatures::enableOverlayScrollbars(bool enable)
 {
     RuntimeEnabledFeatures::setOverlayScrollbarsEnabled(enable);
 }
 
-void WebRuntimeFeatures::enableInputModeAttribute(bool enable)
-{
-    RuntimeEnabledFeatures::setInputModeAttributeEnabled(enable);
-}
-
 void WebRuntimeFeatures::enableOverlayFullscreenVideo(bool enable)
 {
     RuntimeEnabledFeatures::setOverlayFullscreenVideoEnabled(enable);
 }
 
 void WebRuntimeFeatures::enableSharedWorker(bool enable)
 {
     RuntimeEnabledFeatures::setSharedWorkerEnabled(enable);
 }
 
 void WebRuntimeFeatures::enableRepaintAfterLayout(bool enable)
 {
     RuntimeEnabledFeatures::setRepaintAfterLayoutEnabled(enable);
 }
 
 void WebRuntimeFeatures::enableExperimentalWebSocket(bool enable)
 {
     RuntimeEnabledFeatures::setExperimentalWebSocketEnabled(enable);
 }
 
 void WebRuntimeFeatures::enableTargetedStyleRecalc(bool enable)
 {
     RuntimeEnabledFeatures::setTargetedStyleRecalcEnabled(enable);
 }
 
 } // namespace blink