Only update codecInfo when needed

This avoids calling getDecoderInfo repeatedly in the case
where shouldInitCodec return false (e.g. because we don't
have a surface and cannot instantiate a dummy surface).

Issue: #677

-------------
Created by MOE: https:/google/moe
MOE_MIGRATED_REVID=157847702

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

@@ -314,36 +314,36 @@ protected final void maybeInitCodec() throws ExoPlaybackException {
  }
  }
 
- MediaCodecInfo codecInfo = null;
- try {
- codecInfo = getDecoderInfo(mediaCodecSelector, format, drmSessionRequiresSecureDecoder);
- if (codecInfo == null && drmSessionRequiresSecureDecoder) {
- // The drm session indicates that a secure decoder is required, but the device does not have
- // one. Assuming that supportsFormat indicated support for the media being played, we know
- // that it does not require a secure output path. Most CDM implementations allow playback to
- // proceed with a non-secure decoder in this case, so we try our luck.
- codecInfo = getDecoderInfo(mediaCodecSelector, format, false);
- if (codecInfo != null) {
- Log.w(TAG, "Drm session requires secure decoder for " + mimeType + ", but "
- + "no secure decoder available. Trying to proceed with " + codecInfo.name + ".");
+ if (codecInfo == null) {
+ try {
+ codecInfo = getDecoderInfo(mediaCodecSelector, format, drmSessionRequiresSecureDecoder);
+ if (codecInfo == null && drmSessionRequiresSecureDecoder) {
+ // The drm session indicates that a secure decoder is required, but the device does not
+ // have one. Assuming that supportsFormat indicated support for the media being played, we
+ // know that it does not require a secure output path. Most CDM implementations allow
+ // playback to proceed with a non-secure decoder in this case, so we try our luck.
+ codecInfo = getDecoderInfo(mediaCodecSelector, format, false);
+ if (codecInfo != null) {
+ Log.w(TAG, "Drm session requires secure decoder for " + mimeType + ", but "
+ + "no secure decoder available. Trying to proceed with " + codecInfo.name + ".");
+ }
  }
+ } catch (DecoderQueryException e) {
+ throwDecoderInitError(new DecoderInitializationException(format, e,
+ drmSessionRequiresSecureDecoder, DecoderInitializationException.DECODER_QUERY_ERROR));
  }
- } catch (DecoderQueryException e) {
- throwDecoderInitError(new DecoderInitializationException(format, e,
- drmSessionRequiresSecureDecoder, DecoderInitializationException.DECODER_QUERY_ERROR));
- }
 
- if (codecInfo == null) {
- throwDecoderInitError(new DecoderInitializationException(format, null,
- drmSessionRequiresSecureDecoder,
- DecoderInitializationException.NO_SUITABLE_DECODER_ERROR));
+ if (codecInfo == null) {
+ throwDecoderInitError(new DecoderInitializationException(format, null,
+ drmSessionRequiresSecureDecoder,
+ DecoderInitializationException.NO_SUITABLE_DECODER_ERROR));
+ }
  }
 
  if (!shouldInitCodec(codecInfo)) {
  return;
  }
 
- this.codecInfo = codecInfo;
  String codecName = codecInfo.name;
  codecNeedsDiscardToSpsWorkaround = codecNeedsDiscardToSpsWorkaround(codecName, format);
  codecNeedsFlushWorkaround = codecNeedsFlushWorkaround(codecName);

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

@@ -55,8 +55,7 @@ MediaCodecInfo getDecoderInfo(String mimeType, boolean requiresSecureDecoder)
  /**
  * Selects a decoder to instantiate for audio passthrough.
  *
- * @return A {@link MediaCodecInfo} describing the decoder, or null if no suitable decoder
- * exists.
+ * @return A {@link MediaCodecInfo} describing the decoder, or null if no suitable decoder exists.
  * @throws DecoderQueryException Thrown if there was an error querying decoders.
  */
  MediaCodecInfo getPassthroughDecoderInfo() throws DecoderQueryException;

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

@@ -99,7 +99,7 @@ public static void warmDecoderInfoCache(String mimeType, boolean secure) {
 
  /**
  * Returns information about a decoder suitable for audio passthrough.
- **
+ *
  * @return A {@link MediaCodecInfo} describing the decoder, or null if no suitable decoder
  * exists.
  */