Make Map.toSortedMap accept Map out-projected by key type as the receiver.

Update related completion testData.

idea/idea-completion/testData/basic/java/ExtensionFromStandardLibrary.kt

@@ -8,6 +8,6 @@ fun firstFun() {
 }
 
 // INVOCATION_COUNT: 1
-// EXIST: { lookupString:"toSortedMap", itemText:"toSortedMap", tailText:"() for Map<K, V> in kotlin.collections" }
-// EXIST: { lookupString:"toSortedMap", itemText:"toSortedMap", tailText:"(comparator: Comparator<in Int>) for Map<K, V> in kotlin.collections" }
+// EXIST: { lookupString:"toSortedMap", itemText:"toSortedMap", tailText:"() for Map<out K, V> in kotlin.collections" }
+// EXIST: { lookupString:"toSortedMap", itemText:"toSortedMap", tailText:"(comparator: Comparator<in Int>) for Map<out K, V> in kotlin.collections" }
 // NOTHING_ELSE

libraries/stdlib/src/kotlin/collections/MapsJVM.kt

@@ -41,7 +41,7 @@ public inline fun <K, V> ConcurrentMap<K, V>.getOrPut(key: K, defaultValue: () -
  *
  * @sample test.collections.MapJVMTest.toSortedMap
  */
-public fun <K : Comparable<K>, V> Map<K, V>.toSortedMap(): SortedMap<K, V> = TreeMap(this)
+public fun <K : Comparable<K>, V> Map<out K, V>.toSortedMap(): SortedMap<K, V> = TreeMap(this)
 
 /**
  * Converts this [Map] to a [SortedMap] using the given [comparator] so that iteration order will be in the order
@@ -49,7 +49,7 @@ public fun <K : Comparable<K>, V> Map<K, V>.toSortedMap(): SortedMap<K, V> = Tre
  *
  * @sample test.collections.MapJVMTest.toSortedMapWithComparator
  */
-public fun <K, V> Map<K, V>.toSortedMap(comparator: Comparator<in K>): SortedMap<K, V>
+public fun <K, V> Map<out K, V>.toSortedMap(comparator: Comparator<in K>): SortedMap<K, V>
         = TreeMap<K, V>(comparator).apply { putAll(this@toSortedMap) }
 
 /**