FIR: rewrite lambda return type inference

* `return` should only be added to the last statement if the return
   type is not Unit

 * If there is a `return` without an argument, then the expected return
   type is Unit and the last expression is not a return argument (unless
   it's an incomplete call, in which case it is inferred to return Unit;
   this behavior is questionable, but inherited from K1)

 * There should be a constraint on return arguments even if the expected
   type is Unit, otherwise errors will be missed

 * When the expected type is known, using the call completion results
   writer is pointless (and probably subtly wrong).

^KT-54742 Fixed

compiler/testData/diagnostics/tests/controlStructures/ifToAnyDiscriminatingUsages.fir.kt

@@ -27,7 +27,7 @@ fun testResultOfAnonFun2() =
 
 fun testReturnFromAnonFun() =
         run(fun () {
-            return <!RETURN_TYPE_MISMATCH!>if (true) 42 else println()<!>
+            return <!ARGUMENT_TYPE_MISMATCH, RETURN_TYPE_MISMATCH!>if (true) 42 else println()<!>
         })
 
 fun <!IMPLICIT_NOTHING_RETURN_TYPE!>testReturn1<!>() =

compiler/testData/diagnostics/tests/inference/coercionToUnit/afterBareReturn.fir.kt

@@ -34,7 +34,7 @@ fun test4() = <!INFERRED_TYPE_VARIABLE_INTO_EMPTY_INTERSECTION!>run<!> {
 
 fun main() {
     // all ok
-    expectUnit(<!ARGUMENT_TYPE_MISMATCH!>test1()<!>)
+    expectUnit(test1())
     expectUnit(test2())
     expectUnit(test3())
     expectUnit(test4())

compiler/testData/diagnostics/tests/inference/completion/postponedArgumentsAnalysis/basic.fir.kt

@@ -139,8 +139,8 @@ fun main() {
      * K <: (C) -> Unit -> TypeVariable(_RP1) >: C
      * K == (B) -> Unit -> TypeVariable(_RP1) == B
      */
-    val x17: (C) -> Unit = <!INITIALIZER_TYPE_MISMATCH, TYPE_MISMATCH!>selectB(id <!ARGUMENT_TYPE_MISMATCH!>{ <!DEBUG_INFO_EXPRESSION_TYPE("B")!>it<!> }<!>, id <!ARGUMENT_TYPE_MISMATCH!>{ it }<!>, id<(B) -> Unit> { x -> x })<!>
-    val x18: (C) -> Unit = <!TYPE_MISMATCH!>select(id <!ARGUMENT_TYPE_MISMATCH!>{ <!DEBUG_INFO_EXPRESSION_TYPE("C")!>it<!> }<!>, <!ARGUMENT_TYPE_MISMATCH!>{ <!DEBUG_INFO_EXPRESSION_TYPE("C")!>it<!> }<!>, id<(B) -> Unit> { x -> x })<!>
+    val x17: (C) -> Unit = <!INITIALIZER_TYPE_MISMATCH, TYPE_MISMATCH!>selectB(id <!ARGUMENT_TYPE_MISMATCH, ARGUMENT_TYPE_MISMATCH!>{ <!DEBUG_INFO_EXPRESSION_TYPE("B")!>it<!> }<!>, id <!ARGUMENT_TYPE_MISMATCH, ARGUMENT_TYPE_MISMATCH!>{ it }<!>, id<(B) -> Unit> { x -> x })<!>
+    val x18: (C) -> Unit = <!TYPE_MISMATCH!>select(id <!ARGUMENT_TYPE_MISMATCH!>{ <!DEBUG_INFO_EXPRESSION_TYPE("C")!>it<!> }<!>, <!ARGUMENT_TYPE_MISMATCH, ARGUMENT_TYPE_MISMATCH!>{ <!DEBUG_INFO_EXPRESSION_TYPE("C")!>it<!> }<!>, id<(B) -> Unit> { x -> x })<!>
 
     // Resolution of extension/non-extension functions combination
     val x19: String.() -> Unit = select(<!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Function1<kotlin.String, kotlin.Unit>")!>id { <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.String")!>this<!> }<!>, <!DEBUG_INFO_EXPRESSION_TYPE("kotlin.Function1<kotlin.String, kotlin.Unit>")!>id(fun(x: String) {})<!>)

compiler/testData/diagnostics/tests/regressions/resolveCollectionLiteralInsideLambda.fir.kt

@@ -3,5 +3,5 @@
 fun foo(l: () -> Unit) {}
 fun bar(l: () -> String) {}
 
-val a = foo { <!UNSUPPORTED!>[]<!> }
-val b = bar { <!UNSUPPORTED!>[]<!> }
+val a = foo { <!ARGUMENT_TYPE_MISMATCH, UNSUPPORTED!>[]<!> }
+val b = bar { <!ARGUMENT_TYPE_MISMATCH, UNSUPPORTED!>[]<!> }