Add generic mapping for gamepad

ui/events/ozone/gamepad/gamepad_mapping.h

Index: ui/events/ozone/gamepad/gamepad_mapping.h
diff --git a/ui/events/ozone/gamepad/gamepad_mapping.h b/ui/events/ozone/gamepad/gamepad_mapping.h
index e864e977e7ae4ff3ece2242e9d9a7749b21a6de3..14d508b48709f6cdcd6f4e78c3883065c175a9a4 100644
--- a/ui/events/ozone/gamepad/gamepad_mapping.h
+++ b/ui/events/ozone/gamepad/gamepad_mapping.h
@@ -9,19 +9,47 @@
 
 namespace ui {
 
+class EventDeviceInfo;
+
 // The following HATX and HATY is not part of web gamepad definition, but we
 // need to specially treat them cause HAT_Y can be mapped to DPAD_UP or
 // DPAD_DOWN, and HAT_X can be mapped to DAPD_LEFT or DPAD_RIGHT.
 constexpr int kHAT_X = 4;
 constexpr int kHAT_Y = 5;
 
-typedef bool (*GamepadMapper)(uint16_t key,
-                              uint16_t code,
-                              GamepadEventType* mapped_type,
-                              uint16_t* mapped_code);
+// KeyMap maps evdev key code to web gamepad code.
+struct KeyMapEntry {
+  uint16_t evdev_code;
+  uint16_t mapped_code;
+};
+
+// AbsMap maps evdev abs code to web gamepad (type, code).
+struct AbsMapEntry {
+  uint16_t evdev_code;
+  GamepadEventType mapped_type;
+  uint16_t mapped_code;
+};
+
+using KeyMapType = const KeyMapEntry[];
+using AbsMapType = const AbsMapEntry[];
+
+#define TO_BTN(code, mapped_code) \
+  { code, GamepadEventType::BUTTON, mapped_code }
+
+#define TO_ABS(code, mapped_code) \
+  { code, GamepadEventType::AXIS, mapped_code }
+
+class GamepadMapper {
+ public:
+  virtual bool operator()(uint16_t key,
+                          uint16_t code,

[spang, 2017/06/01 05:08:12]

overloading operator() is going to cause syntactic grief when you wrap it in a
unique ptr (and you should)

Probably just name this Map()

[jkwang, 2017/06/02 22:03:51]

Done.

+                          GamepadEventType* mapped_type,
+                          uint16_t* mapped_code) = 0;
+  virtual ~GamepadMapper() {}
+};
 
 // This function gets the best mapper for the gamepad vendor_id and product_id.
-GamepadMapper GetGamepadMapper(uint16_t vendor_id, uint16_t product_id);
+GamepadMapper* GetGamepadMapper(const EventDeviceInfo& devinfo);
 
 }  // namespace ui