Allow display to turn off for power saving during say all

[LeonarddeR]

Link to issue number:

#10643 (comment)

Summary of the issue:

When in say all, the screen is forced to stay on even when there are no screen updates. For non-visual use, this seems unnecessary.
Some users may wish to have their screen turn off for power saving reasons.

Description of how this pull request fixes the issue:

No longer provide the winKernel.ES_DISPLAY_REQUIRED flag to SetThreadExecutionState

Testing performed:

Tested that say all still continues for the original use case in #10643

Known issues with pull request:

If the screen really updates, such as due to cursor movement, this may not make any difference. Therefore difference is only expected when:

• Say all in browse mode with long paragraphs
• Braille display gestures when reading with the review cursor.

Change log entry:

• Changes
  • Braille display gestures and say all will still prevent the system from going idle, but no longer prevent the screen from disabling. (Prevent system sleep when reading lon pieces of text in say all #10643)

[feerrenrut]

Thanks @LeonarddeR