update ios, android and windows

engine/src/shell/platform/unity/android/uiwidgets_panel.cc

   return PointerData::DeviceKind::kTouch;
 }
 
-  void UIWidgetsPanel::OnKeyDown(int keyCode, bool isKeyDown)
+  void UIWidgetsPanel::OnKeyDown(int keyCode, bool isKeyDown, int64_t modifier) 
   {
     if (process_events_)
     {
           std::chrono::duration_cast<std::chrono::microseconds>(
               std::chrono::high_resolution_clock::now().time_since_epoch())
               .count();
+      event.modifier = modifier;
 
       UIWidgetsEngineSendPointerEvent(engine_, &event, 1);
     }
   }
 
   UIWIDGETS_API(void)
-  UIWidgetsPanel_onKey(UIWidgetsPanel *panel, int keyCode, bool isKeyDown)
-  {
-    panel->OnKeyDown(keyCode, isKeyDown);
+  UIWidgetsPanel_onKey(UIWidgetsPanel* panel, int keyCode, bool isKeyDown, int64_t modifier) {
+    panel->OnKeyDown(keyCode, isKeyDown, modifier);
   }
 
   UIWIDGETS_API(void)

engine/src/shell/platform/unity/android/uiwidgets_panel.h

 
   void VSyncCallback(intptr_t baton);
   
-  void OnKeyDown(int keyCode, bool isKeyDown);
+  void OnKeyDown(int keyCode, bool isKeyDown, int64_t modifier);
 
   void OnMouseMove(float x, float y, int button);
 

engine/src/shell/platform/unity/darwin/ios/uiwidgets_panel.h

 
   void SetEventLocationFromCursorPosition(UIWidgetsPointerEvent* event_data);
 
-  void OnKeyDown(int keyCode, bool isKeyDown);
+  void OnKeyDown(int keyCode, bool isKeyDown, int64_t modifier);
 
   void OnMouseMove(float x, float y, int button);
 

engine/src/shell/platform/unity/darwin/ios/uiwidgets_panel.mm

   return PointerData::DeviceKind::kTouch;
 }
 
-void UIWidgetsPanel::OnKeyDown(int keyCode, bool isKeyDown) {
+void UIWidgetsPanel::OnKeyDown(int keyCode, bool isKeyDown, int64_t modifier) {
   if (process_events_) {
     UIWidgetsPointerEvent event = {};
     event.phase = isKeyDown ? UIWidgetsPointerPhase::kMouseDown : UIWidgetsPointerPhase::kMouseUp;
         std::chrono::duration_cast<std::chrono::microseconds>(
             std::chrono::high_resolution_clock::now().time_since_epoch())
             .count();
+    event.modifier = modifier;
 
     UIWidgetsEngineSendPointerEvent(engine_, &event, 1);
   }
 
 
 UIWIDGETS_API(void)
-UIWidgetsPanel_onKey(UIWidgetsPanel* panel, int keyCode, bool isKeyDown) {
-  panel->OnKeyDown(keyCode, isKeyDown);
+UIWidgetsPanel_onKey(UIWidgetsPanel* panel, int keyCode, bool isKeyDown, int64_t modifier) {
+  panel->OnKeyDown(keyCode, isKeyDown, modifier);
 }
 
 UIWIDGETS_API(void)

engine/src/shell/platform/unity/windows/uiwidgets_panel.cc

   }
 }
 
-void UIWidgetsPanel::OnKeyDown(int keyCode, bool isKeyDown) {
+void UIWidgetsPanel::OnKeyDown(int keyCode, bool isKeyDown, int64_t modifier) {
   if (process_events_) {
     UIWidgetsPointerEvent event = {};
     event.phase = isKeyDown ? UIWidgetsPointerPhase::kMouseDown : UIWidgetsPointerPhase::kMouseUp;
         std::chrono::duration_cast<std::chrono::microseconds>(
             std::chrono::high_resolution_clock::now().time_since_epoch())
             .count();
+    event.modifier = modifier;
 
     UIWidgetsEngineSendPointerEvent(engine_, &event, 1);
   }
 
 
 UIWIDGETS_API(void)
-UIWidgetsPanel_onKey(UIWidgetsPanel* panel, int keyCode, bool isKeyDown) {
-  panel->OnKeyDown(keyCode, isKeyDown);
+UIWidgetsPanel_onKey(UIWidgetsPanel* panel, int keyCode, bool isKeyDown, int64_t modifier) {
+  panel->OnKeyDown(keyCode, isKeyDown, modifier);
 }
 
 UIWIDGETS_API(void)

engine/src/shell/platform/unity/windows/uiwidgets_panel.h

   
   void SetEventLocationFromCursorPosition(UIWidgetsPointerEvent* event_data);
   
-  void OnKeyDown(int keyCode, bool isKeyDown);
+  void OnKeyDown(int keyCode, bool isKeyDown, int64_t modifier);
 
   void OnMouseMove(float x, float y);