Fix type inference issues for 'if' and 'when'.

Use 'expectedType' (when present) as an explicit type argument for a special construct call.
Unfortunately, this approach can't be used for elvis due to other elvis-related inference hacks.
Fixes KT-10807, KT-10811.
This also affects KT-6189: now we can infer proper type for 'if'.

If type inference for special call failed, and we found no type errors in sub-expressions,
report TYPE_INFERENCE_FAILED_ON_SPECIAL_CONSTRUCT error.
This (and the hack above) fixes KT-10809: code no longer compiles.

compiler/testData/diagnostics/tests/resolve/specialConstructions/multipleSuperClasses.kt

@@ -8,9 +8,21 @@ interface D: A, B
 interface E: A, B
 
 fun foo(c: C?, d: D?, e: E?) {
-    val a: A? = <!TYPE_MISMATCH!>c ?: d<!> ?: e
+    val test1: A? = <!TYPE_MISMATCH!>c ?: d<!> ?: e
 
-    val b: B? = if (false) <!TYPE_MISMATCH!>if (true) c else d<!> else e
+    val test2: B? = if (false) if (true) c else d else e
 
-    //outer elvis operator and if-expression have error types
+    val test3: A? = when {
+        true -> c
+        else -> when {
+            true -> d
+            else -> e
+        }
+    }
+
+    val test4: B? = when (1) {
+        1 -> c
+        2 -> d
+        else -> e
+    }
 }