A few tiny bug fixes.

library/src/main/java/com/google/android/exoplayer/MediaCodecVideoTrackRenderer.java

@@ -329,7 +329,8 @@ public class MediaCodecVideoTrackRenderer extends MediaCodecTrackRenderer {
     super.onInputFormatChanged(holder);
     // TODO: Ideally this would be read in onOutputFormatChanged, but there doesn't seem
     // to be a way to pass a custom key/value pair value through to the output format.
-    currentPixelWidthHeightRatio = holder.format.pixelWidthHeightRatio;
+    currentPixelWidthHeightRatio = holder.format.pixelWidthHeightRatio == MediaFormat.NO_VALUE ? 1
+        : holder.format.pixelWidthHeightRatio;
   }
 
   @Override

library/src/main/java/com/google/android/exoplayer/util/ManifestFetcher.java

@@ -97,9 +97,6 @@ public class ManifestFetcher<T> extends AsyncTask<String, Void, T> {
         HttpURLConnection connection = configureHttpConnection(new URL(urlString));
         inputStream = connection.getInputStream();
         inputEncoding = connection.getContentEncoding();
-        if (inputEncoding == null) {
-          inputEncoding = C.UTF8_NAME;
-        }
         return parser.parse(inputStream, inputEncoding, contentId, baseUri);
       } finally {
         if (inputStream != null) {