Deprecate Int.latch and Int.indices extensions.

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

@@ -72,6 +72,7 @@ public val Collection<*>.indices: IntRange
 /**
  * Returns an [IntRange] that starts with zero and ends at the value of this number but does not include it.
  */
+deprecated("Use 0..n-1 range instead.")
 public val Int.indices: IntRange
     get() = 0..this - 1
 

libraries/stdlib/src/kotlin/concurrent/Locks.kt

@@ -58,6 +58,7 @@ public inline fun <T> ReentrantReadWriteLock.write(action: () -> T): T {
  *
  * @return the return value of the action.
  */
+deprecated("Use CountDownLatch(Int) instead and await it manually.")
 public fun <T> Int.latch(operation: CountDownLatch.() -> T): T {
     val latch = CountDownLatch(this)
     val result = latch.operation()