Properly dispose filestream after getting mediainfo.

src/NzbDrone.Core.Test/MediaFiles/MediaInfo/VideoFileInfoReaderFixture.cs

@@ -88,5 +88,17 @@ namespace NzbDrone.Core.Test.MediaFiles.MediaInfo
             info.Width.Should().Be(480);
 
         }
+
+        [Test]
+        public void should_dispose_file_after_scanning_mediainfo()
+        {
+            var path = Path.Combine(Directory.GetCurrentDirectory(), "Files", "Media", "H264_sample.mp4");
+
+            var info = Subject.GetMediaInfo(path);
+
+            var stream = new FileStream(path, FileMode.Open, FileAccess.Write);
+
+            stream.Close();
+        }
     }
 }

src/NzbDrone.Core/MediaFiles/MediaInfo/VideoFileInfoReader.cs

@@ -41,7 +41,12 @@ namespace NzbDrone.Core.MediaFiles.MediaInfo
 
                 mediaInfo.Option("ParseSpeed", "0.2");
 
-                int open = mediaInfo.Open(_diskProvider.OpenReadStream(filename));
+                int open;
+
+                using (var stream = _diskProvider.OpenReadStream(filename))
+                {
+                    open = mediaInfo.Open(stream);
+                }
 
                 if (open != 0)
                 {