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"
 
 namespace ui {
 
 bool IsTouchDevicePresent() {
   return ui::DeviceDataManager::GetInstance()->touchscreen_devices().size() > 0;
 }
 
 int MaxTouchPoints() {
-  int max_touch = -1;
+  int max_touch = 0;
   const std::vector<ui::TouchscreenDevice>& touchscreen_devices =
       ui::DeviceDataManager::GetInstance()->touchscreen_devices();
   for (const ui::TouchscreenDevice& device : touchscreen_devices) {
     if (device.touch_points > max_touch)
       max_touch = device.touch_points;
   }
   return max_touch;
 }
 
 // TODO(mustaq@chromium.org): Use mouse detection logic. crbug.com/440503
@@ skipping 32 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