Correctly handle @Repeatable @SerialInfo annotations on classes

that were affected by deduplication of inherited serial info annotations.

Prohibit combination of @InheritableSerialInfo and @Repeatable.

Fixes https://github.com/Kotlin/kotlinx.serialization/issues/2099

plugins/kotlinx-serialization/testData/boxIr/repeatableSerialInfo.kt

@@ -0,0 +1,41 @@
+// TARGET_BACKEND: JVM_IR
+
+// WITH_STDLIB
+// FULL_JDK
+
+import kotlinx.serialization.*
+
+@SerialInfo
+@Target(AnnotationTarget.CLASS, AnnotationTarget.PROPERTY)
+@Repeatable
+annotation class RepeatableSerialInfo(val value: Int)
+
+@SerialInfo
+@Target(AnnotationTarget.CLASS, AnnotationTarget.PROPERTY)
+@java.lang.annotation.Repeatable(JavaRepeatableContainer::class)
+annotation class JavaRepeatable(val value2: Int)
+
+@Target(AnnotationTarget.CLASS, AnnotationTarget.PROPERTY)
+annotation class JavaRepeatableContainer(val value: Array<JavaRepeatable>)
+
+@Serializable
+@RepeatableSerialInfo(1)
+@RepeatableSerialInfo(2)
+@RepeatableSerialInfo(3)
+@JavaRepeatable(2)
+@JavaRepeatable(3)
+data class RepeatableSerialInfoClass(
+    @RepeatableSerialInfo(4) @RepeatableSerialInfo(5) @JavaRepeatable(6) @JavaRepeatable(7) val name: String = "Some Name"
+)
+
+fun List<Annotation>.sum(): Int = filterIsInstance<RepeatableSerialInfo>().sumOf { it.value }
+fun List<Annotation>.sumJava(): Int = filterIsInstance<JavaRepeatable>().sumOf { it.value2 }
+
+fun box(): String {
+    val d = RepeatableSerialInfoClass.serializer().descriptor
+    if (d.annotations.sum() != 6) return "Incorrect number of RepeatableSerialInfo on class: ${d.annotations}"
+    if (d.annotations.sumJava() != 5) return "Incorrect number of JavaRepeatable on class: ${d.annotations}"
+    if (d.getElementAnnotations(0).sum() != 9) return "Incorrect number of RepeatableSerialInfo on property: ${d.getElementAnnotations(0)}"
+    if (d.getElementAnnotations(0).sumJava() != 13) return "Incorrect number of JavaRepeatable on property: ${d.getElementAnnotations(0)}"
+    return "OK"
+}

plugins/kotlinx-serialization/testData/diagnostics/repeatableSerialInfo.kt

@@ -0,0 +1,22 @@
+// FIR_DISABLE_LAZY_RESOLVE_CHECKS
+// FIR_IDENTICAL
+// SKIP_TXT
+
+// WITH_STDLIB
+// FULL_JDK
+
+import kotlinx.serialization.*
+
+<!INHERITABLE_SERIALINFO_CANT_BE_REPEATABLE!>@InheritableSerialInfo<!>
+@Target(AnnotationTarget.CLASS, AnnotationTarget.PROPERTY)
+@Repeatable
+annotation class RepeatableSerialInfo(val value: Int)
+
+<!INHERITABLE_SERIALINFO_CANT_BE_REPEATABLE!>@InheritableSerialInfo<!>
+@Target(AnnotationTarget.CLASS, AnnotationTarget.PROPERTY)
+@java.lang.annotation.Repeatable(JavaRepeatableContainer::class)
+annotation class JavaRepeatable(val value2: Int)
+
+@Target(AnnotationTarget.CLASS, AnnotationTarget.PROPERTY)
+annotation class JavaRepeatableContainer(val value: Array<JavaRepeatable>)
+