Pull down popup from common.

Assets/Cryville/Crtr/Browsing/LegacyResourceManager.cs

@@ -121,7 +121,7 @@ namespace Cryville.Crtr.Browsing {
 					resources = converter.ConvertFrom(file);
 				}
 				catch (Exception ex) {
-					CallHelper.ShowMessageBox(ex.Message);
+					Popup.Create(ex.Message);
 					return false;
 				}
 				foreach (var res in resources) {

Assets/Cryville/Crtr/Browsing/ResourceBrowser.cs

@@ -59,11 +59,11 @@ namespace Cryville.Crtr.Browsing {
 		private void OnAddDialogClosed() {
 			if (_dialog.FileName == null) return;
 			if (ResourceManager.ImportItemFrom(_dialog.FileName)) {
-				CallHelper.ShowMessageBox("Import succeeded");
+				Popup.Create("Import succeeded");
 				OnPathClicked(ResourceManager.CurrentDirectory.Length - 1);
 			}
 			else {
-				CallHelper.ShowMessageBox("Import failed");
+				Popup.Create("Import failed");
 			}
 		}
 	}