Fix pre-L codec buffer initialization

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=203341457

library/core/src/main/java/com/google/android/exoplayer2/mediacodec/MediaCodecRenderer.java

@@ -729,7 +729,7 @@ public abstract class MediaCodecRenderer extends BaseRenderer {
       codec.start();
       TraceUtil.endSection();
       codecInitializedTimestamp = SystemClock.elapsedRealtime();
-      getCodecBuffers();
+      getCodecBuffers(codec);
     } catch (Exception e) {
       if (codec != null) {
         resetCodecBuffers();
@@ -743,7 +743,7 @@ public abstract class MediaCodecRenderer extends BaseRenderer {
     onCodecInitialized(name, codecInitializedTimestamp, elapsed);
   }
 
-  private void getCodecBuffers() {
+  private void getCodecBuffers(MediaCodec codec) {
     if (Util.SDK_INT < 21) {
       inputBuffers = codec.getInputBuffers();
       outputBuffers = codec.getOutputBuffers();