JS backend: fix kt-5345 (Type mismatch on Int / Float division)

js/js.translator/testData/number/cases/intDivFloat.kt

@@ -0,0 +1,18 @@
+// http://youtrack.jetbrains.com/issue/KT-5345
+// KT-5345 (Javascript) Type mismatch on Int / Float division
+// If any of Number operands is floating-point, the result should be float too.
+
+package foo
+
+fun box(): String {
+    assertEquals(0.5f, 1 / 2.0f, "Int / Float")
+    assertEquals(0.5, 1 / 2.0, "Int / Double")
+
+    assertEquals(0.5f, (1: Short) / 2.0f, "Short / Float")
+    assertEquals(0.5, (1: Short) / 2.0, "Short / Double")
+
+    assertEquals(0.5f, (1: Byte) / 2.0f, "Byte / Float")
+    assertEquals(0.5, (1: Byte) / 2.0, "Byte / Double")
+
+    return "OK"
+}