fix: windows il2cpp build lead to empty scene

com.unity.uiwidgets/Runtime/engine/UIWidgetsPanelWrapper.cs

         int width, int height, float dpi, string streamingAssetsPath, string font_settings);
 
     [DllImport(NativeBindings.dllName)]
+    [return: MarshalAs(UnmanagedType.U1)]
     static extern bool UIWidgetsPanel_releaseNativeTexture(IntPtr ptr);
 
     [DllImport(NativeBindings.dllName)]

com.unity.uiwidgets/Runtime/ui/painting.cs

         static extern void Path_reset(IntPtr ptr);
 
         [DllImport(NativeBindings.dllName)]
+        [return: MarshalAs(UnmanagedType.U1)]
         static extern bool Path_contains(IntPtr ptr, float x, float y);
 
         [DllImport(NativeBindings.dllName)]
         static extern unsafe void Path_getBounds(IntPtr ptr, float* rect);
 
         [DllImport(NativeBindings.dllName)]
+        [return: MarshalAs(UnmanagedType.U1)]
         static extern bool Path_op(IntPtr ptr, IntPtr path1, IntPtr path2, int operation);
     }
 
 
         
         [DllImport(NativeBindings.dllName)]
+        [return: MarshalAs(UnmanagedType.U1)]
+        [return: MarshalAs(UnmanagedType.U1)]
         static extern bool PathMeasure_nativeNextContour();
     }
 
         public static extern void Vertices_dispose(IntPtr ptr);
 
         [DllImport(NativeBindings.dllName)]
+        [return: MarshalAs(UnmanagedType.U1)]
         public static extern unsafe bool Vertices_init(IntPtr ptr,
             int mode,
             float* positions,
             }
         }
 
-        public int approximateBytesUsed => Picture_GetAllocationSize(_ptr);
+        public ulong approximateBytesUsed => Picture_GetAllocationSize(_ptr);
-        static extern int Picture_GetAllocationSize(IntPtr ptr);
+        [return: MarshalAs(UnmanagedType.SysUInt)]
+        static extern ulong Picture_GetAllocationSize(IntPtr ptr);
 
         delegate void Picture_toImageCallback(IntPtr callbackHandle, IntPtr result);
 
         static extern void PictureRecorder_dispose(IntPtr ptr);
 
         [DllImport(NativeBindings.dllName)]
+        [return: MarshalAs(UnmanagedType.U1)]
         static extern bool PictureRecorder_isRecording(IntPtr ptr);
 
         [DllImport(NativeBindings.dllName)]

com.unity.uiwidgets/Runtime/ui/text.cs

         }
     }
 
+    [StructLayout(LayoutKind.Sequential)]
     public struct Float32List {
         public IntPtr data;
         public int length;
         static extern float Paragraph_ideographicBaseline(IntPtr ptr);
 
         [DllImport(dllName: NativeBindings.dllName)]
+        [return: MarshalAs(UnmanagedType.U1)]
         static extern bool Paragraph_didExceedMaxLines(IntPtr ptr);
 
         [DllImport(dllName: NativeBindings.dllName)]

com.unity.uiwidgets/Runtime/ui/window.cs

             return null;
         }
 
-        List<string> _computePlatformResolvedLocale(List<string> supportedLocalesData) =>
-            Window_computePlatformResolvedLocale(supportedLocalesData);
+        // Window_computePlatformResolvedLocale not implement yet, TODO _computePlatformResolvedLocale
+        List<string> _computePlatformResolvedLocale(List<string> supportedLocalesData) {
+            return Window_computePlatformResolvedLocale(supportedLocalesData)?? new List<string>();
+        }
 
         /// A callback that is invoked whenever [locale] changes value.
         ///

engine/src/lib/ui/painting/picture.cc

 
 UIWIDGETS_API(void) Picture_dispose(Picture* ptr) { ptr->Release(); }
 
-UIWIDGETS_API(bool) Picture_GetAllocationSize(Picture* ptr) {
+UIWIDGETS_API(size_t) Picture_GetAllocationSize(Picture* ptr) {
   return ptr->GetAllocationSize();
 }
 

engine/src/lib/ui/window/window.cc

 
 // TODO: ComputePlatformResolvedLocale
 UIWIDGETS_API(void) Window_computePlatformResolvedLocale(Window* ptr, Scene* scene) {
-  ptr->client()->Render(scene);
 }
 
 }  // namespace