x11: Move XInput2 availability information out of the message pump.

ui/events/x/device_data_manager.h

 // Copyright 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.
 
 #ifndef UI_EVENTS_X_DEVICE_DATA_MANAGER_H_
 #define UI_EVENTS_X_DEVICE_DATA_MANAGER_H_
 
 #include <X11/extensions/XInput2.h>
 
 #include <bitset>
 #include <map>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/event_types.h"
 #include "ui/events/event_constants.h"
-#include "ui/events/events_export.h"
+#include "ui/events/events_base_export.h"
 #include "ui/gfx/x/x11_atom_cache.h"
 
 template <typename T> struct DefaultSingletonTraits;
 
 typedef union _XEvent XEvent;
 
 namespace ui {
 
 // CrOS touchpad metrics gesture types
 enum GestureMetricsType {
   kGestureMetricsTypeNoisyGround = 0,
   kGestureMetricsTypeUnknown,
 };
 
 // A class that extracts and tracks the input events data. It currently handles
 // mouse, touchpad and touchscreen devices.
-class EVENTS_EXPORT DeviceDataManager {
+class EVENTS_BASE_EXPORT DeviceDataManager {
  public:
   // Enumerate additional data that one might be interested on an input event,
   // which are usually wrapped in X valuators. If you modify any of this,
   // make sure to update the kCachedAtoms data structure in the source file
   // and the k*Type[Start/End] constants used by IsCMTDataType and
   // IsTouchDataType.
   enum DataType {
     // Define the valuators used the CrOS CMT driver. Used by mice and CrOS
     // touchpads.
     DT_CMT_SCROLL_X = 0,  // Scroll amount on the X (horizontal) direction.
@@ skipping 51 matching lines @@
 
   // Returns the DeviceDataManager singleton.
   static DeviceDataManager* GetInstance();
 
   // Natural scroll setter/getter.
   bool natural_scroll_enabled() const { return natural_scroll_enabled_; }
   void set_natural_scroll_enabled(bool enabled) {
     natural_scroll_enabled_ = enabled;
   }
 
+  // Returns if XInput2 is available on the system.
+  bool IsXInput2Available() const;
+
   // Get the natural scroll direction multiplier (1.0f or -1.0f).
   float GetNaturalScrollFactor(int sourceid) const;
 
   // Updates the list of devices.
   void UpdateDeviceList(Display* display);
 
   // For multitouch events we use slot number to distinguish touches from
   // different fingers. This function returns true if the associated slot
   // for |xiev| can be found and it is saved in |slot|, returns false if
   // no slot can be found.
@@ skipping 162 matching lines @@
 
   unsigned char button_map_[256];
   int button_map_count_;
 
   DISALLOW_COPY_AND_ASSIGN(DeviceDataManager);
 };
 
 }  // namespace ui
 
 #endif  // UI_EVENTS_X_DEVICE_DATA_MANAGER_H_