Drop hover:on-demand support & let touch-screens report "none" instead.

ui/base/touch/touch_device_linux.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/base/touch/touch_device.h"
 
 #include "base/logging.h"
 #include "ui/events/devices/input_device_manager.h"
 
 namespace ui {
@@ skipping 10 matching lines @@
   int available_pointer_types = POINTER_TYPE_FINE;
   if (IsTouchDevicePresent())
     available_pointer_types |= POINTER_TYPE_COARSE;
 
   DCHECK(available_pointer_types);
   return available_pointer_types;
 }
 
 // TODO(mustaq@chromium.org): Use mouse detection logic. crbug.com/495634
 int GetAvailableHoverTypes() {
-  // Assume a mouse is there
   int available_hover_types = HOVER_TYPE_HOVER;
   if (IsTouchDevicePresent())
-    available_hover_types |= HOVER_TYPE_ON_DEMAND;
-
-  DCHECK(available_hover_types);
+    available_hover_types |= HOVER_TYPE_NONE;
   return available_hover_types;
 }
 
 }  // namespace
 
 TouchScreensAvailability GetTouchScreensAvailability() {
   if (!IsTouchDevicePresent())
     return TouchScreensAvailability::NONE;
 
   return InputDeviceManager::GetInstance()->AreTouchscreensEnabled()
@@ skipping 21 matching lines @@
     return POINTER_TYPE_FINE;
   if (available_pointer_types & POINTER_TYPE_COARSE)
     return POINTER_TYPE_COARSE;
   DCHECK_EQ(available_pointer_types, POINTER_TYPE_NONE);
   return POINTER_TYPE_NONE;
 }
 
 HoverType GetPrimaryHoverType(int available_hover_types) {
   if (available_hover_types & HOVER_TYPE_HOVER)
     return HOVER_TYPE_HOVER;
-  if (available_hover_types & HOVER_TYPE_ON_DEMAND)
-    return HOVER_TYPE_ON_DEMAND;
   DCHECK_EQ(available_hover_types, HOVER_TYPE_NONE);
   return HOVER_TYPE_NONE;
 }
 
 }  // namespace ui