Reflection: fix classifier and rendering of suspend function types

Also fix a mistake in the `JavaToKotlinClassMap.mapKotlinToJava`'s kdoc.

 #KT-79020 Fixed
 #KT-79206 Fixed

Author: udalov

analysis/low-level-api-fir/tests-gen/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLBlackBoxTestGenerated.java

@@ -2,6 +2,7 @@
 // WITH_REFLECT
 package test
 
+import kotlin.coroutines.SuspendFunction0
 import kotlin.reflect.KClass
 import kotlin.test.assertEquals
 import kotlin.test.assertTrue
@@ -60,7 +61,7 @@ fun f(): @Anno(
     AnnotationTarget.EXPRESSION,
     Nested("1"),
     ["lmao"],
-    [Double::class, Unit::class, LongArray::class, Array<String>::class],
+    [Double::class, Unit::class, LongArray::class, Array<String>::class, Function0::class, SuspendFunction0::class],
     [AnnotationTarget.TYPEALIAS, AnnotationTarget.FIELD],
     [Nested("2"), Nested("3")]
 ) Unit {}
@@ -71,7 +72,7 @@ fun box(): String {
         "@test.Anno(b=1, c=x, d=3.14, f=-2.72, i=42424242, j=239239239239239, s=42, z=true, " +
                 "ba=[-1], ca=[y], da=[-3.14159], fa=[2.7218], ia=[424242], ja=[239239239239], sa=[-43], za=[false, true], " +
                 "str=lol, k=class java.lang.Number, k2=class [I, e=EXPRESSION, [email protected](value=1), stra=[lmao], " +
-                "ka=[class java.lang.Double, class kotlin.Unit, class [J, class [Ljava.lang.String;], " +
+                "ka=[class java.lang.Double, class kotlin.Unit, class [J, class [Ljava.lang.String;, interface kotlin.jvm.functions.Function0, interface kotlin.jvm.functions.Function1], " +
                 "ea=[TYPEALIAS, FIELD], aa=[@test.Nested(value=2), @test.Nested(value=3)])",
         anno.toString()
     )

analysis/low-level-api-fir/tests-gen/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLReversedBlackBoxTestGenerated.java

@@ -0,0 +1,36 @@
+// TARGET_BACKEND: JVM
+// WITH_REFLECT
+
+import kotlin.reflect.*
+import kotlin.test.assertEquals
+import kotlin.test.assertTrue
+
+class A {
+    fun function0(): (() -> Unit) = null!!
+    fun function1(): ((String) -> Unit)? = null
+    fun function3(): ((Any, Int, Unit?) -> LongArray)? = null
+    fun suspendFunction0(): (suspend () -> Unit)? = null
+    fun suspendFunction1(): (suspend (String) -> Unit) = null!!
+    fun suspendFunction3(): (suspend (Any, Int, Unit?) -> LongArray)? = null
+}
+
+fun check(function: KCallable<*>, typeToString: String, classFqName: String, arguments: String) {
+    val type = function.returnType
+    assertEquals(typeToString.endsWith("?"), type.isMarkedNullable, "Fail: isMarkedNullable for $type")
+    val classifier = type.classifier as? KClass<*> ?: error("Fail: no classifier for $type")
+    assertEquals(classFqName, classifier.qualifiedName, "Fail: qualified name for $type")
+    assertEquals(arguments, type.arguments.toString(), "Fail: arguments for $type")
+    assertEquals(typeToString, type.toString())
+}
+
+fun box(): String {
+    check(A::function0, "() -> kotlin.Unit", "kotlin.Function0", "[kotlin.Unit]")
+    check(A::function1, "((kotlin.String) -> kotlin.Unit)?", "kotlin.Function1", "[kotlin.String, kotlin.Unit]")
+    check(A::function3, "((kotlin.Any, kotlin.Int, kotlin.Unit?) -> kotlin.LongArray)?", "kotlin.Function3", "[kotlin.Any, kotlin.Int, kotlin.Unit?, kotlin.LongArray]")
+    // After KT-79225, classifier should be "kotlin.coroutines.SuspendFunction{arity}"
+    check(A::suspendFunction0, "(suspend () -> kotlin.Unit)?", "kotlin.Function1", "[kotlin.Unit]")
+    check(A::suspendFunction1, "suspend (kotlin.String) -> kotlin.Unit", "kotlin.Function2", "[kotlin.String, kotlin.Unit]")
+    check(A::suspendFunction3, "(suspend (kotlin.Any, kotlin.Int, kotlin.Unit?) -> kotlin.LongArray)?", "kotlin.Function4", "[kotlin.Any, kotlin.Int, kotlin.Unit?, kotlin.LongArray]")
+
+    return "OK"
+}

compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirLightTreeBlackBoxCodegenTestGenerated.java

@@ -142,7 +142,8 @@ object JavaToKotlinClassMap {
      * - kotlin.Nothing -> java.lang.Void
      * - kotlin.IntArray -> null
      * - kotlin.Function3 -> kotlin.jvm.functions.Function3
-     * - kotlin.coroutines.SuspendFunction3 -> kotlin.jvm.functions.Function4
+     * - kotlin.coroutines.SuspendFunction3 -> null
+     *     - NOT kotlin.jvm.functions.Function4, to make sure that Continuation type argument is correctly added manually at the call site.
      * - kotlin.Function42 -> kotlin.jvm.functions.FunctionN
      * - kotlin.coroutines.SuspendFunction42 -> kotlin.jvm.functions.FunctionN
      * - kotlin.reflect.KFunction3 -> kotlin.reflect.KFunction