JS: move expressions test to box tests

js/js.translator/testData/box/dynamic/binaryOperations.kt

@@ -0,0 +1,20 @@
+package foo
+
+fun box(): String {
+    val a: dynamic = 12
+    var b: dynamic = 33.4
+    var c: dynamic = "text"
+    val d: dynamic = true
+
+    assertEquals(60, a * 5)
+    assertEquals(-21.4, a - b)
+    assertEquals("12text", a + c)
+    assertEquals("text foo", c + " foo")
+    assertEquals("text33.4", c + b)
+    assertEquals("12[object Object]", a + bar)
+    assertEquals(2, a % 5)
+    assertEquals("42.35928143712575text[object Object]", a / b + d * n + c + bar)
+    assertEquals("12text[object Object]4233.4", a + c + bar + n + b)
+
+    return "OK"
+}