### Use Tools Wisely

As Uncle Ben said:

<blockquote>
With great <strike>power</strike> <strong>tools</strong> comes great responsibility.
</blockquote>

Avoid inadvertently doing harm.

   * hold {@code expectedSize} elements without growth. This behavior cannot be broadly guaranteed,
   * but it is observed to be true for OpenJDK 1.7. It also can't be guaranteed that the method
   * isn't inadvertently <i>oversizing</i> the returned map.
   *
   * @param expectedSize the number of entries you expect to add to the returned map
   * @return a new, empty {@code HashMap} with enough capacity to hold {@code expectedSize} entries

   * hold {@code expectedSize} elements without growth. This behavior cannot be broadly guaranteed,
   * but it is observed to be true for OpenJDK 1.7. It also can't be guaranteed that the method
   * isn't inadvertently <i>oversizing</i> the returned map.
   *
   * @param expectedSize the number of entries you expect to add to the returned map
   * @return a new, empty {@code HashMap} with enough capacity to hold {@code expectedSize} entries

*   Improves stability of GCS filesystem on Mac.
*   Add time estimation to HloCostAnalysis.
*   Fixed the bug in Estimator that params in constructor was not a deepcopy of
    the user provided one. This bugs inadvertently enabled user to mutate the
    params after the creation of Estimator, leading to potentially undefined
    behavior.
*   Added None check for save_path in `saver.restore`.