Minor in JS backend: added missed test case -- when inside when w/o braces.

js/js.tests/test/org/jetbrains/k2js/test/semantics/PatternMatchingTest.java

@@ -105,4 +105,8 @@ public final class PatternMatchingTest extends SingleFileTranslationTest {
     public void testIfWithOneStmWhen() throws Exception {
         fooBoxTest();
     }
-}
+
+    public void testWhenWithOneStmWhen() throws Exception {
+        fooBoxTest();
+    }
+}

js/js.translator/testData/patternMatching/cases/whenWithOneStmWhen.kt

@@ -0,0 +1,22 @@
+package foo
+
+
+fun box(): Boolean {
+    var result = false
+    val i = 1
+    when (i) {
+        1 ->
+            when (i) {
+                1 ->    result = true
+                else -> result = false
+            }
+
+        else ->
+            when (i) {
+                1 ->    result = true
+                else -> result = false
+            }
+    }
+
+    return result;
+}