[Ozone] Properly initialize multitouch slot values

ui/events/ozone/evdev/event_device_info.h

Index: ui/events/ozone/evdev/event_device_info.h
diff --git a/ui/events/ozone/evdev/event_device_info.h b/ui/events/ozone/evdev/event_device_info.h
index 321711404d5c23c66cc8d347f1840e976b78bb60..e00b6eb5418349cc5eea83548e648bb758583ff4 100644
--- a/ui/events/ozone/evdev/event_device_info.h
+++ b/ui/events/ozone/evdev/event_device_info.h
@@ -12,6 +12,9 @@
 #include "ui/events/ozone/evdev/event_device_util.h"
 #include "ui/events/ozone/evdev/events_ozone_evdev_export.h"
 
+// ABS_MT_SLOT isn't valid options for EVIOCGMTSLOTS ioctl.
+#define ABS_MT_COUNT (ABS_MT_TOOL_Y - ABS_MT_SLOT)

[spang, 2014/10/21 19:38:36]

This looks deceptively like something that comes from input.h (and would collide
if they decide to add it). So please differentiate.

Maybe EVDEV_ABS_MT_COUNT

[dnicoara, 2014/10/21 20:32:12]

Done.

+
 namespace ui {
 
 // Device information for Linux input devices
@@ -38,6 +41,7 @@ class EVENTS_OZONE_EVDEV_EXPORT EventDeviceInfo {
   // Properties of absolute axes.
   int32 GetAbsMinimum(unsigned int code) const;
   int32 GetAbsMaximum(unsigned int code) const;
+  int32 GetSlotValue(unsigned int code, unsigned int slot) const;
 
   // Check input device properties.
   bool HasProp(unsigned int code) const;
@@ -64,6 +68,9 @@ class EVENTS_OZONE_EVDEV_EXPORT EventDeviceInfo {
 
   struct input_absinfo abs_info_[ABS_CNT];
 
+  // Store the values for the multi-touch properties for each slot.
+  int32_t* slot_values_[ABS_MT_COUNT];
+
   DISALLOW_COPY_AND_ASSIGN(EventDeviceInfo);
 };