ozone: evdev: Allow setting slot values in EventDeviceInfo

ui/events/ozone/evdev/touch_event_converter_evdev.cc

 // Copyright 2014 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/events/ozone/evdev/touch_event_converter_evdev.h"
 
 #include <errno.h>
 #include <fcntl.h>
 #include <linux/input.h>
 #include <poll.h>
@@ skipping 92 matching lines @@
     y_num_tuxels_ -= cal.bezel_top + cal.bezel_bottom;
 
     VLOG(1) << "applying touch calibration: "
             << base::StringPrintf("[%d, %d, %d, %d]", cal.bezel_left,
                                   cal.bezel_right, cal.bezel_top,
                                   cal.bezel_bottom);
   }
 
   events_.resize(touch_points_);
   for (size_t i = 0; i < events_.size(); ++i) {
-    events_[i].x = info.GetSlotValue(ABS_MT_POSITION_X, i);
-    events_[i].y = info.GetSlotValue(ABS_MT_POSITION_Y, i);
-    events_[i].tracking_id = info.GetSlotValue(ABS_MT_TRACKING_ID, i);
+    events_[i].x = info.GetAbsMtSlotValue(ABS_MT_POSITION_X, i);
+    events_[i].y = info.GetAbsMtSlotValue(ABS_MT_POSITION_Y, i);
+    events_[i].tracking_id = info.GetAbsMtSlotValue(ABS_MT_TRACKING_ID, i);
     events_[i].touching = (events_[i].tracking_id >= 0);
     events_[i].slot = i;
-    events_[i].radius_x = info.GetSlotValue(ABS_MT_TOUCH_MAJOR, i);
-    events_[i].radius_y = info.GetSlotValue(ABS_MT_TOUCH_MINOR, i);
-    events_[i].pressure = info.GetSlotValue(ABS_MT_PRESSURE, i);
+
+    // Optional bits.
+    events_[i].radius_x =
+        info.GetAbsMtSlotValueWithDefault(ABS_MT_TOUCH_MAJOR, i, 0);
+    events_[i].radius_y =
+        info.GetAbsMtSlotValueWithDefault(ABS_MT_TOUCH_MINOR, i, 0);
+    events_[i].pressure =
+        info.GetAbsMtSlotValueWithDefault(ABS_MT_PRESSURE, i, 0);
   }
 }
 
 bool TouchEventConverterEvdev::Reinitialize() {
   EventDeviceInfo info;
   if (info.Initialize(fd_)) {
     Initialize(info);
     return true;
   }
   return false;
@@ skipping 167 matching lines @@
 
     if (event_type != ET_UNKNOWN)
       ReportEvent(*event, event_type, delta);
 
     event->was_touching = event->touching;
     event->altered = false;
   }
 }
 
 }  // namespace ui