[JS IR] Add tests for KT-48941

js/js.translator/testData/box/jsCode/literalInVal.kt

@@ -0,0 +1,11 @@
+fun foo(): String {
+    val q1 = "O"
+    val q2 = "K"
+    val qq = q1 + q2
+    val b = js("\"$qq\"")
+    return b
+}
+
+
+
+fun box() = foo()

js/js.translator/testData/box/jsCode/literalInValField.kt

@@ -0,0 +1,11 @@
+val p1 = "O"
+val p2 = "K"
+val pp = p1 + p2
+
+fun bar(): String {
+    val v = pp
+    val b = js("\"$v\"")
+    return b
+}
+
+fun box(): String = bar()