Deprecate kotlin.reflect.findAnnotation with ERROR

(cherry picked from commit cfe1591)

Author: udalov

compiler/testData/codegen/box/reflection/annotations/findAnnotation.kt

@@ -1,7 +1,7 @@
 // IGNORE_BACKEND: JS
 // WITH_REFLECT
 
-import kotlin.reflect.findAnnotation
+import kotlin.reflect.full.findAnnotation
 import kotlin.test.assertNull
 
 annotation class Yes(val value: String)

core/reflection.jvm/src/kotlin/reflect/KAnnotatedElements.kt

@@ -20,7 +20,7 @@ package kotlin.reflect
 /**
  * Returns an annotation of the given type on this element.
  */
-@Deprecated("Use 'findAnnotation' from kotlin.reflect.full package", ReplaceWith("this.findAnnotation<T>()", "kotlin.reflect.full.findAnnotation"), level = DeprecationLevel.WARNING)
+@Deprecated("Use 'findAnnotation' from kotlin.reflect.full package", ReplaceWith("this.findAnnotation<T>()", "kotlin.reflect.full.findAnnotation"), level = DeprecationLevel.ERROR)
 @SinceKotlin("1.1")
 inline fun <reified T : Annotation> KAnnotatedElement.findAnnotation(): T? =
         @Suppress("UNCHECKED_CAST")