Remove backend tests on old inference

Also remove any mentions of NewInference, and rename some tests.

compiler/testData/ir/irText/expressions/funInterface/samConversionsWithSmartCasts.kt.txt

@@ -68,6 +68,28 @@ fun test6(a: Any) {
   run1(r = a /*as Function0<Unit> */ /*-> KRunnable */)
 }
 
+fun test7(a: Function1<Int, Int>) {
+  a as Function0<Unit> /*~> Unit */
+  run1(r = a /*as Function0<Unit> */ /*-> KRunnable */)
+}
+
+fun <T : Function1<Int, Int>> test7a(a: T) {
+  a as Function0<Unit> /*~> Unit */
+  run1(r = a /*as Function0<Unit> */ /*-> KRunnable */)
+}
+
+fun <T> test7b(a: T) where T : Function1<Int, Unit>, T : Function0<Unit> {
+  run1(r = a /*-> KRunnable */)
+}
+
+interface Unrelated {
+
+}
+
+fun <T> test7c(a: T) where T : Unrelated, T : Function0<Unit> {
+  run1(r = a /*-> KRunnable */)
+}
+
 fun test8(a: Function0<Unit>) {
   run1(r = id<Function0<Unit>>(x = a) /*-> KRunnable */)
 }