[descriptors] Move some annotation-related utilities to the core module

- AnnotationDescriptor#argumentValue is not frontend-specific
- AnnotationDescriptor#getAnnotationStringValue is not Native-specific

We are going to need these functions in the IR code, so it makes
sense to factor them out to the core module.

core/descriptors/src/org/jetbrains/kotlin/resolve/annotations/Utils.kt

@@ -0,0 +1,28 @@
+/*
+ * Copyright 2010-2023 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.resolve.annotations
+
+import org.jetbrains.kotlin.descriptors.annotations.AnnotationDescriptor
+import org.jetbrains.kotlin.name.Name
+import org.jetbrains.kotlin.resolve.constants.ConstantValue
+import org.jetbrains.kotlin.resolve.constants.ErrorValue
+import org.jetbrains.kotlin.resolve.constants.StringValue
+import org.jetbrains.kotlin.utils.atMostOne
+
+fun AnnotationDescriptor.argumentValue(parameterName: String): ConstantValue<*>? {
+    return allValueArguments[Name.identifier(parameterName)].takeUnless { it is ErrorValue }
+}
+
+fun AnnotationDescriptor.getAnnotationStringValue(name: String): String {
+    return (argumentValue(name) as? StringValue)?.value ?: error("Expected value $name at annotation $this")
+}
+
+inline fun <reified T> AnnotationDescriptor.getArgumentValueOrNull(name: String): T? {
+    val constantValue = this.allValueArguments.entries.atMostOne {
+        it.key.asString() == name
+    }?.value
+    return constantValue?.value as T?
+}