add 'Api' variable to use in builder

common/Native/native.js

@@ -279,6 +279,7 @@ function GetNativeEngine()
 }
 
 var native_renderer = null;
+var Api = null;
 var _api = null;
 
 function NativeOpenFileData(data, version)
@@ -295,6 +296,7 @@ function NativeOpenFileData(data, version)
         _api = new window["Asc"]["spreadsheet_api"]({});
         _api.asc_nativeOpenFile(data, version);
     }
+    Api = _api;
 }
 
 function NativeOpenFile()
@@ -312,6 +314,7 @@ function NativeOpenFile()
         _api = new window["Asc"]["spreadsheet_api"]();
         _api.asc_nativeOpenFile(doc_bin);
     }
+    Api = _api;
 }
 
 function NativeOpenFile2(_params)
@@ -340,6 +343,8 @@ function NativeOpenFile2(_params)
         _api = new window["Asc"]["spreadsheet_api"]();
         _api.asc_nativeOpenFile(doc_bin);
     }
+
+    Api = _api;
 }
 
 function NativeCalculateFile()