Support member extension properties, implement KClass.getExtensionProperties()

#KT-6570 Fixed

compiler/testData/codegen/boxWithStdlib/reflection/methodsFromAny/memberExtensionToString.kt

@@ -0,0 +1,12 @@
+import kotlin.reflect.jvm.kotlin
+
+class A {
+    var String.id: String
+        get() = this
+        set(value) {}
+}
+
+fun box(): String {
+    val p = javaClass<A>().kotlin.getExtensionProperties().single()
+    return if ("$p" == "var A.(kotlin.String.)id") "OK" else "Fail $p"
+}

compiler/testData/codegen/boxWithStdlib/reflection/properties/getExtensionPropertiesMutableVsReadonly.kt

@@ -0,0 +1,27 @@
+import kotlin.reflect.jvm.kotlin
+import kotlin.reflect.KMutableMemberExtensionProperty
+
+var storage = "before"
+
+class A {
+    val String.readonly: String
+        get() = this
+
+    var String.mutable: String
+        get() = storage
+        set(value) { storage = value }
+}
+
+fun box(): String {
+    val props = javaClass<A>().kotlin.getExtensionProperties()
+    val readonly = props.single { it.name == "readonly" }
+    assert(readonly !is KMutableMemberExtensionProperty<A, *, *>) { "Fail 1: $readonly" }
+    val mutable = props.single { it.name == "mutable" }
+    assert(mutable is KMutableMemberExtensionProperty<A, *, *>) { "Fail 2: $mutable" }
+
+    val a = A()
+    mutable as KMutableMemberExtensionProperty<A, String, String>
+    assert(mutable[a, ""] == "before") { "Fail 3: ${mutable.get(a, "")}" }
+    mutable[a, ""] = "OK"
+    return mutable.get(a, "")
+}

compiler/testData/codegen/boxWithStdlib/reflection/properties/memberAndMemberExtensionWithSameName.kt

@@ -0,0 +1,25 @@
+import kotlin.reflect.jvm.kotlin
+import kotlin.reflect.KMemberProperty
+import kotlin.reflect.KMemberExtensionProperty
+
+class A {
+    val foo: String = "member"
+    val Unit.foo: String get() = "extension"
+}
+
+fun box(): String {
+    run {
+        val foo: KMemberProperty<A, *> = javaClass<A>().kotlin.getProperties().single()
+        assert(foo.name == "foo") { "Fail name: $foo (${foo.name})" }
+        assert(foo.get(A()) == "member") { "Fail value: ${foo[A()]}" }
+    }
+
+    run {
+        val foo: KMemberExtensionProperty<A, *, *> = javaClass<A>().kotlin.getExtensionProperties().single()
+        assert(foo.name == "foo") { "Fail name: $foo (${foo.name})" }
+        foo as KMemberExtensionProperty<A, Unit, *>
+        assert(foo.get(A(), Unit) == "extension") { "Fail value: ${foo[A(), Unit]}" }
+    }
+
+    return "OK"
+}