[minor] [NI] Additional test for loosing type annotations on extension functions

taken from KT-34820

compiler/testData/diagnostics/tests/inference/substitutions/kt32189returnTypeWithTypealiasSubtitution.kt

@@ -20,3 +20,18 @@ fun buildB() {
     B.Builder().a2()
     B.Builder().a3()
 }
+
+// additional example from #KT-34820
+
+class R
+class P
+
+typealias F = R.(P) -> Unit
+
+fun guess(): F? = TODO()
+fun consume(f: F) {}
+
+fun problem() {
+    val p = guess()
+    consume(p ?: {})
+}

compiler/testData/diagnostics/tests/inference/substitutions/kt32189returnTypeWithTypealiasSubtitution.txt

@@ -4,6 +4,9 @@ public fun applyRestrictions1(): ApplyRestrictions /* = B.Builder.() -> B.Builde
 public fun applyRestrictions2(): ApplyRestrictions /* = B.Builder.() -> B.Builder */
 public fun </*0*/ K> applyRestrictions3(/*0*/ e: K): ApplyRestrictions /* = B.Builder.() -> B.Builder */
 public fun buildB(): kotlin.Unit
+public fun consume(/*0*/ f: F /* = R.(P) -> kotlin.Unit */): kotlin.Unit
+public fun guess(): F? /* = (R.(P) -> kotlin.Unit)? */
+public fun problem(): kotlin.Unit
 
 public final class B {
     public constructor B()
@@ -18,4 +21,19 @@ public final class B {
         public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
     }
 }
+
+public final class P {
+    public constructor P()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+public final class R {
+    public constructor R()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
 public typealias ApplyRestrictions = B.Builder.() -> B.Builder
+public typealias F = R.(P) -> kotlin.Unit