Add proto comparison tests with changes of class/member flags

Original commit: 58a91b3d20

jps/jps-plugin/testData/comparison/classSignatureChange/classFlagsChanged/old.kt

@@ -1,4 +1,55 @@
 package test
 
-class ClassWithFlagsChanged {
+class AbstractFlagAdded
+abstract class AbstractFlagRemoved
+abstract class AbstractFlagUnchanged
+
+class AnnotationFlagAdded
+annotation class AnnotationFlagRemoved
+annotation class AnnotationFlagUnchanged
+
+class DataFlagAdded(val x: Int)
+data class DataFlagRemoved(val x: Int)
+data class DataFlagUnchanged(val x: Int)
+
+class EnumFlagAdded
+enum class EnumFlagRemoved
+enum class EnumFlagUnchanged
+
+class FinalFlagAdded
+final class FinalFlagRemoved
+final class FinalFlagUnchanged
+
+class InnerClassHolder {
+    class InnerFlagAdded
+    inner class InnerFlagRemoved
+    inner class InnerFlagUnchanged
 }
+
+class InternalFlagAdded
+internal class InternalFlagRemoved
+internal class InternalFlagUnchanged
+
+class OpenFlagAdded
+open class OpenFlagRemoved
+open class OpenFlagUnchanged
+
+class PrivateFlagAdded
+private class PrivateFlagRemoved
+private class PrivateFlagUnchanged
+
+class ProtectedClassHolder {
+    class ProtectedFlagAdded
+    protected class ProtectedFlagRemoved
+    protected class ProtectedFlagUnchanged
+}
+
+class PublicFlagAdded
+public class PublicFlagRemoved
+public class PublicFlagUnchanged
+
+class SealedFlagAdded
+sealed class SealedFlagRemoved
+sealed class SealedFlagUnchanged
+
+class UnchangedNoFlags