title: EACCES (Permission denied) even after giving permission
body: <p>I have an Android app targeting SDK 28 so I have the permissions to deal with. I check that the <code>READ_EXTERNAL_STORAGE</code> is set, but when Exoplayer tries to read the file (which I verified did exist) I see </p>
  
  <blockquote>
    <p>com.google.android.exoplayer2.upstream.FileDataSource$FileDataSourceException:
    java.io.FileNotFoundException:
    /storage/emulated/0/DCIM/Camera/VID_20190610_200249.mp4: open failed:
    EACCES (Permission denied).</p>
  </blockquote>
  
  <p>I can play an asset (file baked into the app) just fine as well as playing from the Internet. I just cannot play a local video stored in my ...DCIM/Camera directory for some reason. Can anyone tell me what I am doing wrong please? My code looks like this:</p>
  
  <pre><code>player = ExoPlayerFactory.newSimpleInstance(this, DefaultTrackSelector())
      playerView.player = player
      player?.addListener(this)
  
      //TODO: Change this when we are given the embedded video
      val dataSource = DefaultDataSourceFactory(this, Util.getUserAgent(this, "Exoplayer"))
      var path: String = ""
      var mediaSource: ExtractorMediaSource
  
      if (passedUrl == PLAY_TUTORIAL) {
          path = "asset:///tutorial_video.mp4"
          mediaSource = ExtractorMediaSource.Factory(dataSource).createMediaSource(Uri.parse(path))
      } else {
          path = passedUrl
  
          val file = File(path)
          val uriPath = Uri.fromFile(file)
  
          Timber.d("Path is $uriPath and that file exists = ${file.exists()}")
  
  
          mediaSource = ExtractorMediaSource.Factory(dataSource).createMediaSource(uriPath)
      }
  
      //Setting this to 0 will keep the controls from being hidden otherwise it's in milliseconds
      playerView.controllerShowTimeoutMs = 1500
  
      player?.prepare(mediaSource)
  </code></pre>
  
  <p>When I run the code I see this in the logs:</p>
  
  <pre><code>2019-06-13 21:54:35.048 5774-5774/com.android.myapp D/ViewTutorialActivity: Path is file:///storage/emulated/0/DCIM/Camera/VID_20190610_200249.mp4 and that file exists = true
  
  2019-06-13 21:54:35.076 5774-5846/com.android.myapp D/OpenGLRenderer: Setting buffer count to 3, min_undequeued 1, extraBuffers 0
  
  2019-06-13 21:54:38.077 5774-5968/com.android.myapp E/ExoPlayerImplInternal: Source error.
  com.google.android.exoplayer2.upstream.FileDataSource$FileDataSourceException: java.io.FileNotFoundException: /storage/emulated/0/DCIM/Camera/VID_20190610_200249.mp4: open failed: EACCES (Permission denied)
      at com.google.android.exoplayer2.upstream.FileDataSource.open(FileDataSource.java:73)
  </code></pre>
  
  <p>Any idea?</p>