Implemented smooth scrolling using xinput2 in X11.

ui/events/x/events_x.cc

Index: ui/events/x/events_x.cc
diff --git a/ui/events/x/events_x.cc b/ui/events/x/events_x.cc
index e6fb3120d3e095b61fb387351a0be66f2fae5835..1dee583fd609f159e81451af894d9e686d370e7b 100644
--- a/ui/events/x/events_x.cc
+++ b/ui/events/x/events_x.cc
@@ -444,6 +444,9 @@ EventType EventTypeFromNative(const base::NativeEvent& native_event) {
             return devices->IsTouchpadXInputEvent(native_event) ? ET_SCROLL
                                                                 : ET_MOUSEWHEEL;
           }
+          if (devices->IsScrollClassEvent(native_event)) {
+            return ET_MOUSEWHEEL;
+          }

[sadrul, 2014/12/22 17:11:12]

no {}

           if (devices->IsCMTMetricsEvent(native_event))
             return ET_UMA_DATA;
           if (GetButtonMaskForX2Event(xievent))
@@ -716,18 +719,35 @@ gfx::Vector2d GetMouseWheelOffset(const base::NativeEvent& native_event) {
                          static_cast<int>(y_offset));
   }
 
+  double x_scroll_offset, y_scroll_offset;
+  if (DeviceDataManagerX11::GetInstance()->IsScrollClassEvent(native_event)) {
+    DeviceDataManagerX11::GetInstance()->GetScrollClassOffsets(
+        native_event,
+        &x_scroll_offset, &y_scroll_offset);
+    return gfx::Vector2d(
+        static_cast<int>(x_scroll_offset * kWheelScrollAmount),
+        static_cast<int>(y_scroll_offset * kWheelScrollAmount));
+  }
+

[sadrul, 2014/12/22 17:11:12]

Can this block move into GetScrollOffsets() instead?

   int button = native_event->type == GenericEvent ?
       EventButtonFromNative(native_event) : native_event->xbutton.button;
 
+  bool verticalScrollClass =
+    DeviceDataManagerX11::GetInstance()
+    ->IsScrollClassVerticalDevice(native_event);
+  bool horizontalScrollClass =

[sadrul, 2014/12/22 17:11:12]

Should be vertical_scroll_class etc.

+    DeviceDataManagerX11::GetInstance()
+    ->IsScrollClassHorizontalDevice(native_event);
+
   switch (button) {
     case 4:
-      return gfx::Vector2d(0, kWheelScrollAmount);
+      return gfx::Vector2d(0, verticalScrollClass ? 0 : kWheelScrollAmount);
     case 5:
-      return gfx::Vector2d(0, -kWheelScrollAmount);
+      return gfx::Vector2d(0, verticalScrollClass ? 0 : -kWheelScrollAmount);
     case 6:
-      return gfx::Vector2d(kWheelScrollAmount, 0);
+      return gfx::Vector2d(horizontalScrollClass ? 0 : kWheelScrollAmount, 0);
     case 7:
-      return gfx::Vector2d(-kWheelScrollAmount, 0);
+      return gfx::Vector2d(horizontalScrollClass ? 0 : -kWheelScrollAmount, 0);
     default:
       return gfx::Vector2d();
   }