JS: Force Rhino to load files using UTF8 encoding. Fixes failing kt14597 on windows agents.

Author: anton-bannykh

js/js.tests/test/org/jetbrains/kotlin/js/test/rhino/RhinoUtils.java

@@ -18,6 +18,7 @@
 
 import com.google.common.collect.Sets;
 import com.intellij.openapi.util.io.FileUtil;
+import com.intellij.openapi.vfs.CharsetToolkit;
 import com.intellij.util.containers.ContainerUtil;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -106,7 +107,7 @@ private static void runFileWithRhino(@NotNull String inputFile,
             @NotNull Scriptable scope) throws Exception {
         String result;
         try {
-            result = FileUtil.loadFile(new File(inputFile), true);
+            result = FileUtil.loadFile(new File(inputFile), CharsetToolkit.UTF8, true);
         }
         catch (IOException e) {
             throw new RuntimeException(e);