FIC: add codegen tests, adapt previously tests for SAMs

compiler/testData/codegen/box/funInterface/partialSam.kt

@@ -0,0 +1,41 @@
+// !LANGUAGE: +NewInference +FunctionInterfaceConversion +SamConversionPerArgument +SamConversionForKotlinFunctions
+// WITH_RUNTIME
+
+fun interface Fn<T, R> {
+    fun run(s: String, i: Int, t: T): R
+}
+
+class J {
+    fun runConversion(f1: Fn<String, Int>, f2: Fn<Int, String>): Int {
+        return f1.run("Bar", 1, f2.run("Foo", 42, 239))
+    }
+}
+
+fun box(): String {
+    val j = J()
+    var x = ""
+
+    val fsi = object : Fn<String, Int> {
+        override fun run(s: String, i: Int, t: String): Int {
+            x += "$s$i$t "
+            return i
+        }
+    }
+
+    val fis = object : Fn<Int, String> {
+        override fun run(s: String, i: Int, t: Int): String {
+            x += "$s$i$t "
+            return s
+        }
+    }
+
+    val r1 = j.runConversion(fsi) { s, i, ti -> x += "L$s$i$ti "; "L$s"}
+    val r2 = j.runConversion({ s, i, ts -> x += "L$s$i$ts"; i }, fis)
+
+    if (r1 != 1) return "fail r1: $r1"
+    if (r2 != 1) return "fail r2: $r2"
+
+    if (x != "LFoo42239 Bar1LFoo Foo42239 LBar1Foo") return x
+
+    return "OK"
+}