Fix annotations on Java elements in reflection

#KT-10840 Fixed

compiler/testData/codegen/boxWithJava/reflection/annotationsOnJavaMembers/J.java

@@ -0,0 +1,11 @@
+@Anno("J")
+public class J {
+    @Anno("foo")
+    public static int foo = 42;
+
+    @Anno("bar")
+    public static void bar() {}
+
+    @Anno("constructor")
+    public J() {}
+}

compiler/testData/codegen/boxWithJava/reflection/annotationsOnJavaMembers/K.kt

@@ -0,0 +1,12 @@
+import kotlin.test.assertEquals
+
+annotation class Anno(val value: String)
+
+fun box(): String {
+    assertEquals("[@Anno(value=J)]", J::class.annotations.toString())
+    assertEquals("[@Anno(value=foo)]", J::foo.annotations.toString())
+    assertEquals("[@Anno(value=bar)]", J::bar.annotations.toString())
+    assertEquals("[@Anno(value=constructor)]", ::J.annotations.toString())
+
+    return "OK"
+}

compiler/tests/org/jetbrains/kotlin/codegen/generated/BlackBoxWithJavaCodegenTestGenerated.java

@@ -581,6 +581,12 @@ public class BlackBoxWithJavaCodegenTestGenerated extends AbstractBlackBoxCodege
             KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/codegen/boxWithJava/reflection"), Pattern.compile("^([^\\.]+)$"), true);
         }
 
+        @TestMetadata("annotationsOnJavaMembers")
+        public void testAnnotationsOnJavaMembers() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/boxWithJava/reflection/annotationsOnJavaMembers/");
+            doTestWithJava(fileName);
+        }
+
         @TestMetadata("callInstanceJavaMethod")
         public void testCallInstanceJavaMethod() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/boxWithJava/reflection/callInstanceJavaMethod/");

core/descriptors.runtime/src/org/jetbrains/kotlin/load/java/components/RuntimeSourceElementFactory.kt

@@ -23,7 +23,7 @@ import org.jetbrains.kotlin.load.java.structure.JavaElement
 import org.jetbrains.kotlin.load.java.structure.reflect.ReflectJavaElement
 
 object RuntimeSourceElementFactory : JavaSourceElementFactory {
-    private class RuntimeSourceElement(override val javaElement: ReflectJavaElement) : JavaSourceElement {
+    class RuntimeSourceElement(override val javaElement: ReflectJavaElement) : JavaSourceElement {
         override fun toString() = javaClass.name + ": " + javaElement.toString()
         override fun getContainingFile(): SourceFile = SourceFile.NO_SOURCE_FILE
     }

core/descriptors.runtime/src/org/jetbrains/kotlin/load/java/structure/reflect/ReflectJavaAnnotation.kt

@@ -21,7 +21,7 @@ import org.jetbrains.kotlin.load.java.structure.JavaAnnotationArgument
 import org.jetbrains.kotlin.name.Name
 import java.lang.reflect.Method
 
-class ReflectJavaAnnotation(private val annotation: Annotation) : ReflectJavaElement(), JavaAnnotation {
+class ReflectJavaAnnotation(val annotation: Annotation) : ReflectJavaElement(), JavaAnnotation {
     override fun findArgument(name: Name): JavaAnnotationArgument? {
         return getArgumentValue(annotation.annotationClass.java.getDeclaredMethod(name.asString()))
     }

core/reflection.jvm/src/kotlin/reflect/jvm/internal/KAnnotatedElementImpl.kt

@@ -17,6 +17,8 @@
 package kotlin.reflect.jvm.internal
 
 import org.jetbrains.kotlin.descriptors.annotations.Annotated
+import org.jetbrains.kotlin.load.java.components.RuntimeSourceElementFactory
+import org.jetbrains.kotlin.load.java.structure.reflect.ReflectJavaAnnotation
 import org.jetbrains.kotlin.load.kotlin.reflect.ReflectAnnotationSource
 import kotlin.reflect.KAnnotatedElement
 
@@ -24,7 +26,16 @@ internal interface KAnnotatedElementImpl : KAnnotatedElement {
     val annotated: Annotated
 
     override val annotations: List<Annotation>
-        get() = annotated.annotations.map {
-            (it.source as? ReflectAnnotationSource)?.annotation
-        }.filterNotNull()
+        get() = annotated.annotations.mapNotNull {
+            val source = it.source
+            when (source) {
+                is ReflectAnnotationSource -> {
+                    source.annotation
+                }
+                is RuntimeSourceElementFactory.RuntimeSourceElement -> {
+                    (source.javaElement as? ReflectJavaAnnotation)?.annotation
+                }
+                else -> null
+            }
+        }
 }