Compile unsigned types sourceset with 1.3 and annotate them with SinceKotlin("1.3")

libraries/stdlib/unsigned/src/kotlin/UByteArray.kt

@@ -8,6 +8,7 @@
 package kotlin
 
 @Suppress("NON_PUBLIC_PRIMARY_CONSTRUCTOR_OF_INLINE_CLASS")
+@SinceKotlin("1.3")
 public inline class UByteArray internal constructor(private val storage: ByteArray) : Collection<UByte> {
 
     /** Returns the array element at the given [index]. This method can be called using the index operator. */
@@ -37,11 +38,13 @@ public inline class UByteArray internal constructor(private val storage: ByteArr
     override fun isEmpty(): Boolean = this.storage.size == 0
 }
 
+@SinceKotlin("1.3")
 public /*inline*/ fun UByteArray(size: Int, init: (Int) -> UByte): UByteArray {
     return UByteArray(ByteArray(size) { index -> init(index).toByte() })
 }
 
 @Suppress("FORBIDDEN_VARARG_PARAMETER_TYPE")
+@SinceKotlin("1.3")
 public fun ubyteArrayOf(vararg elements: UByte): UByteArray {
     return UByteArray(elements.size) { index -> elements[index] }
 }