Merge pull request #500 from MichaelNedzelsky/kt5320

JS Backend: fixed associativity of JsCondition(ternary operator).

Fixed wrong code generation when use JsCondition(ternary operator) as condition of simple `if`(JsCondition).

#KT-5320 fixed

js/js.translator/testData/expression/misc/cases/rightAssocForGeneratedConditionalOperator.kt

@@ -0,0 +1,14 @@
+// http://youtrack.jetbrains.com/issue/KT-5320
+// KT-5320 Invalid JS code generated for typecast inside ternary operator
+
+package foo
+
+fun test(x: Any?): Int = if (x as Boolean) 1 else 2;
+
+fun box(): String {
+    assertEquals(1, test(true), "true")
+    assertEquals(2, test(false), "false")
+    assertEquals("OK", if (if (0 < 1) false else true) "Not OK" else "OK")
+
+    return "OK"
+}