MediaPlayer: add method getVideoSize()

Description

• This request add method getVideoSize() for MediaPlayer.
• This method call native function libvlc_video_get_size().

Motivation and Context

This change allows users to get the video size at runtime using native get size function.

How Has This Been Tested?

• Build libvlc-all successfully.
• Added to maven local and used in Android app.
• Tested with .m3u8 and flv stream: getVideoSize() return correct result.
• If specified video does not exist, return NULL instead of int[]

Screenshots / GIFs (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Enhancement (non-breaking change which cleans up / improves existing functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the CONTRIBUTING section of the README document.

Resolves

Fixes: #2457 (closed)