Migrate boxInline tests to new multi-file framework

compiler/testData/codegen/boxInline/trait/trait.kt

@@ -0,0 +1,44 @@
+// FILE: 1.kt
+
+package test
+
+interface InlineTrait {
+
+    fun finalInline(s: () -> String): String {
+        return s()
+    }
+
+    companion object {
+        inline final fun finalInline(s: () -> String): String {
+            return s()
+        }
+    }
+}
+
+class Z: InlineTrait {
+
+}
+
+// FILE: 2.kt
+
+import test.*
+
+fun testFinalInline(): String {
+    return Z().finalInline({"final"})
+}
+
+fun testFinalInline2(instance: InlineTrait): String {
+    return instance.finalInline({"final2"})
+}
+
+fun testClassObject(): String {
+    return InlineTrait.finalInline({"classobject"})
+}
+
+fun box(): String {
+    if (testFinalInline() != "final") return "test1: ${testFinalInline()}"
+    if (testFinalInline2(Z()) != "final2") return "test2: ${testFinalInline2(Z())}"
+    if (testClassObject() != "classobject") return "test3: ${testClassObject()}"
+
+    return "OK"
+}