Unified touch_device_aurax11 and touch_device_ozone.

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/device_data_manager.h"
 #include "ui/events/devices/x11/touch_factory_x11.h"
 
 namespace ui {
 
 bool IsTouchDevicePresent() {
+  // TODO(sadrul@chromium.org): Support evdev hotplugging.
   return ui::DeviceDataManager::GetInstance()->touchscreen_devices().size() > 0;
 }
 
 int MaxTouchPoints() {
   return ui::TouchFactory::GetInstance()->GetMaxTouchPoints();

[sadrul, 2014/12/19 21:48:44]

I think this is X11 only, and isn't available on ozone. I have a plan to change
the impl of MaxTouchPoints() to make it go through DeviceDataManager. Le me take
a stab at that first. Once that is done, this should be ready to land.

 }
 
 // TODO(mustaq@chromium.org): Use mouse detection logic. crbug.com/440503
 int GetAvailablePointerTypes() {
   // Assume a mouse is there
   int available_pointer_types = POINTER_TYPE_FINE;
   if (IsTouchDevicePresent())
     available_pointer_types |= POINTER_TYPE_COARSE;
 
   DCHECK(available_pointer_types);
@@ skipping 25 matching lines @@
   int available_hover_types = GetAvailableHoverTypes();
   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