[video_player_android] Add adaptive bitrate streaming support

[sheershtehri7]

Implements adaptive bitrate streaming support for the Android video player.

Changes

• setBandwidthLimit — Implements the platform interface method via ExoPlayer's DefaultTrackSelector.setMaxVideoBitrate(). Values <= 0 remove the cap (Integer.MAX_VALUE).
• ABR configuration — Configures AdaptiveTrackSelection.Factory and DefaultBandwidthMeter (initial estimate 1 Mbps) for both texture and platform view modes, enabling ExoPlayer's built-in bandwidth-adaptive track selection.
• PlatformVideoView — Switches from SurfaceView to TextureView to support seamless resolution changes during quality transitions. SurfaceView operates on a separate window layer which can cause visual artifacts when the video resolution changes mid-playback during ABR.
• onVideoSizeChanged no-op — Added to both TextureExoPlayerEventListener and PlatformViewExoPlayerEventListener to prevent re-initialization events during ABR quality switches.
• Null-safety — Adds null check for videoFormat in PlatformViewExoPlayerEventListener.sendInitialized() to handle cases where format is not yet available.

Versioned as 2.10.0 — minor version bump. Requires video_player_platform_interface ^6.7.0.

Depends on PR #11322 (platform interface setBandwidthLimit).

Part of flutter/flutter#183941

AI Disclosure: This PR was developed with assistance from AI tools (GitHub Copilot / Claude). All code has been reviewed, tested, and validated by the author.

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Footnotes

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[gemini-code-assist]

Code Review

This pull request adds support for adaptive bitrate streaming on Android. The changes include implementing setBandwidthLimit, configuring ExoPlayer with AdaptiveTrackSelection.Factory and DefaultBandwidthMeter, and switching to TextureView for platform views to allow seamless resolution changes. The implementation is solid, but there is an opportunity to reduce code duplication in the ExoPlayer creation logic, which I've pointed out in a specific comment.

[gemini-code-assist]

The ExoPlayer creation logic within this lambda is nearly identical to the logic in TextureVideoPlayer.create(). To avoid code duplication and improve maintainability, consider extracting this logic into a shared helper method.

For example, you could create a private static method, perhaps in the VideoPlayer base class, that builds and returns a configured ExoPlayer instance:

@UnstableApi
private static ExoPlayer createExoPlayerWithAbr(Context context, VideoAsset asset) {
    // ... (setup for DefaultBandwidthMeter and DefaultTrackSelector)
    ExoPlayer.Builder builder = 
        new ExoPlayer.Builder(context)
            .setTrackSelector(trackSelector)
            .setBandwidthMeter(bandwidthMeter)
            .setMediaSourceFactory(asset.getMediaSourceFactory(context));
    return builder.build();
}

Then, both create methods could use this helper in their ExoPlayerProvider lambda: () -> createExoPlayerWithAbr(context, asset).

[stuartmorgan-g]

Closing per #11322 (comment)