Added SetFullScreen to GUI::Window and GLFWWindowSystem

[yankailab]

Added SetFullScreen function to GUI::Window, WindowSystem and GLFWWindowSystem, so that classes inherits GUI::Window can set to full screen mode easily.

Type

• Bug fix (non-breaking change which fixes an issue): Fixes #
• New feature (non-breaking change which adds functionality). Resolves #
• Breaking change (fix or feature that would cause existing functionality to not work as expected) Resolves #

Motivation and Context

We would create custom UI classes that inherits the GUI::Window. With the added SetFullScreen interface the UI classes can easily switch to full screen mode and back.

Checklist:

• I have run python util/check_style.py --apply to apply Open3D code style
  to my code.
• This PR changes Open3D behavior or adds new functionality.
  • Both C++ (Doxygen) and Python (Sphinx / Google style) documentation is
    updated accordingly.
  • I have added or updated C++ and / or Python unit tests OR included test
    results (e.g. screenshots or numbers) here.
• I will follow up and update the code if CI fails.
• For fork PRs, I have selected Allow edits from maintainers.

Description

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This change is 

[update-docs]

Thanks for submitting this pull request! The maintainers of this repository would appreciate if you could update the CHANGELOG.md based on your changes.

[errissa]

Hi @yankailab. Thank you for submitting this PR. I notice that you closed your old PR for this feature. Please add Python bindings for the new SetFullScreen method. If you need help with that please let me know.

[ssheorey]

Needs testing on all platforms and Python bindings.

[ssheorey]

FIXME: Crash in macOS on activating full screen.

[ssheorey]

Retest PR after GLFW upgrade PR (#6587 ) is merged.