Repository: flutter
Issue: [iOS] video_player plays mp3 on Android, but not on iOS
Labels: platform-ios,d: api docs,p: video_player,package,P3,team-ios,triaged-ios

The video_player plugin appears to behave differently on Android and iOS depending on the file extension used - Android will load a mis-named file and do a best effort, iOS just silently fails.

While this is definitely an edge case that might not need to be supported at all, the different behavior on the two platforms made hunting down the root cause a little more confusing than usual.

Thanks for considering!

## Steps to Reproduce

1. Create an .mp4 video `file` with an .mp3 `extension`, such as: https://res.cloudinary.com/demo/video/upload/f_mp4/dog.mp3.
2. Add this to the `video_player` [example app](https://github.com/flutter/plugins/tree/master/packages/video_player#example):
```dart
_controller = VideoPlayerController.network(
        'https://res.cloudinary.com/demo/video/upload/f_mp4/dog.mp3')
      ..initialize().then((_) {
        // Ensure the first frame is shown after the video is initialized, even before the play button has been pressed.
        setState(() {});
      });
```
3. Build & run on Android & iOS - the video plays on Android, and does not on iOS.
4. Note that with cloudinary you can provide different extensions - the /f_mp4/ part of the path is forcing the file format. Re-run the app using an .mp4 extension to verify that the iOS build can load the video: https://res.cloudinary.com/demo/video/upload/f_mp4/dog.mp4

## Logs

<!--
      Run your application with `flutter run --verbose` and attach all the
      log output below between the lines with the backticks. If there is an
      exception, please see if the error message includes enough information
      to explain how to solve the issue.
-->

```
⋊> ~/D/video_player_test flutter run --verbose
...
[   +3 ms] 🔥  To hot reload changes while running, press "r". To hot restart (and rebuild state), press "R".
[        ] An Observatory debugger and profiler on bigbubble is available at: http://127.0.0.1:1029/eKHkw2VM5DQ=/
[        ] For a more detailed help message, press "h". To detach, press "d"; to quit, press "q".

```

<!--
     Run `flutter analyze` and attach any output of that command below.
     If there are any analysis errors, try resolving them before filing this issue.
-->

```
⋊> ~/D/video_player_test flutter analyze                                                                                                          13:39:09
Analyzing video_player_test...                                          
No issues found! (ran in 4.9s)
```

<!-- Finally, paste the output of running `flutter doctor -v` here. -->

```
⋊> ~/D/video_player_test flutter doctor -v                                                                                                        13:39:20
[✓] Flutter (Channel stable, v1.7.8+hotfix.4, on Mac OS X 10.14.6 18G87, locale en-US)
    • Flutter version 1.7.8+hotfix.4 at /Users/deg/Development/flutter
    • Framework revision 20e59316b8 (7 weeks ago), 2019-07-18 20:04:33 -0700
    • Engine revision fee001c93f
    • Dart version 2.4.0

 
[✓] Android toolchain - develop for Android devices (Android SDK version 28.0.3)
    • Android SDK at /Users/deg/Library/Android/sdk
    • Android NDK location not configured (optional; useful for native profiling support)
    • Platform android-28, build-tools 28.0.3
    • Java binary at: /Users/deg/Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1343-b01)
    • All Android licenses accepted.

[✓] Xcode - develop for iOS and macOS (Xcode 10.3)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Xcode 10.3, Build version 10G8
    • CocoaPods version 1.7.5

[✓] iOS tools - develop for iOS devices
    • ios-deploy 1.9.4

[✓] Android Studio (version 3.4)
    • Android Studio at /Users/deg/Applications/Android Studio.app/Contents
    • Flutter plugin version 37.1.1
    • Dart plugin version 183.6270
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1343-b01)

[✓] VS Code
    • VS Code at /Users/deg/Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.4.1

[✓] Connected device (1 available)
    • bigbubble • 00008027-001A51A036EB002E • ios • iOS 12.4.1

• No issues found!
```