ozone: events: Centralize & document our NativeEvent woes

ui/events/ozone/events_ozone.cc

Index: ui/events/ozone/events_ozone.cc
diff --git a/ui/events/ozone/events_ozone.cc b/ui/events/ozone/events_ozone.cc
index 57892532c32374e24be8d1b0f3d256ad92ce3516..fb0d1427bd3812547ae6ef7f6372b00d744e7dbf 100644
--- a/ui/events/ozone/events_ozone.cc
+++ b/ui/events/ozone/events_ozone.cc
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "ui/events/ozone/events_ozone.h"
+
 #include "ui/events/event.h"
 #include "ui/events/event_constants.h"
 #include "ui/events/event_utils.h"
@@ -146,8 +148,21 @@ bool GetScrollOffsets(const base::NativeEvent& native_event,
                       float* x_offset_ordinal,
                       float* y_offset_ordinal,
                       int* finger_count) {
-  NOTIMPLEMENTED();
-  return false;
+  const ui::ScrollEvent* event =
+      static_cast<const ui::ScrollEvent*>(native_event);
+  DCHECK(event->IsScrollEvent());
+  if (x_offset)
+    *x_offset = event->x_offset();
+  if (y_offset)
+    *y_offset = event->y_offset();
+  if (x_offset_ordinal)
+    *x_offset_ordinal = event->x_offset_ordinal();
+  if (y_offset_ordinal)
+    *y_offset_ordinal = event->y_offset_ordinal();
+  if (finger_count)
+    *finger_count = event->finger_count();
+
+  return true;
 }
 
 bool GetFlingData(const base::NativeEvent& native_event,
@@ -178,4 +193,24 @@ int GetModifiersFromKeyState() {
   return 0;
 }
 
+void DispatchEventFromNativeUiEvent(const base::NativeEvent& native_event,
+                                    base::Callback<void(ui::Event*)> callback) {
+  const ui::Event* native_ui_event = static_cast<ui::Event*>(native_event);
+  if (native_ui_event->IsKeyEvent()) {
+    ui::KeyEvent key_event(native_event);
+    callback.Run(&key_event);
+  } else if (native_ui_event->IsMouseEvent()) {
+    ui::MouseEvent mouse_event(native_event);
+    callback.Run(&mouse_event);
+  } else if (native_ui_event->IsTouchEvent()) {
+    ui::TouchEvent touch_event(native_event);
+    callback.Run(&touch_event);
+  } else if (native_ui_event->IsScrollEvent()) {
+    ui::ScrollEvent scroll_event(native_event);
+    callback.Run(&scroll_event);
+  } else {
+    NOTREACHED();
+  }
+}
+
 }  // namespace ui