Parcelize: Allow Parcelize annotation on sealed classes

See https://issuetracker.google.com/177856520

plugins/parcelize/parcelize-compiler/testData/box/sealedClass2.kt

@@ -0,0 +1,33 @@
+// WITH_RUNTIME
+
+@file:JvmName("TestKt")
+package test
+
+import kotlinx.parcelize.*
+import android.os.Parcel
+import android.os.Parcelable
+
+@Parcelize
+sealed class Foo : Parcelable {
+    data class A(val x: Int) : Foo()
+    object B : Foo()
+}
+
+data class C(val x: String) : Foo()
+
+@Parcelize
+data class Bar(val a: Foo.A, val b: Foo.B, val c: C, val foo: Foo) : Parcelable
+
+fun box() = parcelTest { parcel ->
+    val first = Bar(Foo.A(1024), Foo.B, C("OK"), Foo.A(1))
+
+    first.writeToParcel(parcel, 0)
+
+    val bytes = parcel.marshall()
+    parcel.unmarshall(bytes, 0, bytes.size)
+    parcel.setDataPosition(0)
+
+    val second = parcelableCreator<Bar>().createFromParcel(parcel)
+
+    assert(first == second)
+}

plugins/parcelize/parcelize-compiler/testData/box/sealedInterface.kt

@@ -0,0 +1,74 @@
+// WITH_RUNTIME
+
+@file:JvmName("TestKt")
+package test
+
+import kotlinx.parcelize.*
+import android.os.Parcel
+import android.os.Parcelable
+
+@Parcelize
+sealed interface I : Parcelable
+
+@Parcelize
+sealed class A : Parcelable
+
+abstract class B
+interface J
+
+data class AI(val x: String) : A(), I
+class I1 : J, I {
+    override fun equals(other: Any?): Boolean {
+        return other is I1
+    }
+}
+data class I2(val x: Float) : B(), I
+
+object A1 : A()
+open class A2(val x: Int) : A() {
+    override fun equals(other: Any?): Boolean {
+        return other is A2 && other::class == A2::class && x == other.x
+    }
+}
+
+@Parcelize
+class A3 : A2(3) {
+    override fun equals(other: Any?): Boolean {
+        return other is A3 && x == other.x
+    }
+}
+
+@Parcelize
+data class C(
+    val a: A,
+    val i: I,
+    val a1: A1,
+    val a2: A2,
+    val a3: A3,
+    val ai: AI,
+    val i1: I1,
+    val i2: I2,
+) : Parcelable
+
+fun box() = parcelTest { parcel ->
+    val first = C(
+        AI("0"),
+        AI("1"),
+        A1,
+        A2(2),
+        A3(),
+        AI("4"),
+        I1(),
+        I2(5.0f),
+    )
+
+    first.writeToParcel(parcel, 0)
+
+    val bytes = parcel.marshall()
+    parcel.unmarshall(bytes, 0, bytes.size)
+    parcel.setDataPosition(0)
+
+    val second = parcelableCreator<C>().createFromParcel(parcel)
+
+    assert(first == second)
+}