Fix Dackka parameter name error in `Gav1Decoder` and `VpxDecoder`

These aren't caught by presubmit because the classes are annotated
`@VisibleForTesting` and are therefore stripped out by Metalava. However
Metalava doesn't run when we're generating javadoc for real.

#minor-release

PiperOrigin-RevId: 487476260

libraries/decoder_av1/src/main/java/androidx/media3/decoder/av1/Gav1Decoder.java

@@ -138,13 +138,13 @@ public final class Gav1Decoder
   }
 
   @Override
-  protected void releaseOutputBuffer(VideoDecoderOutputBuffer buffer) {
+  protected void releaseOutputBuffer(VideoDecoderOutputBuffer outputBuffer) {
     // Decode only frames do not acquire a reference on the internal decoder buffer and thus do not
     // require a call to gav1ReleaseFrame.
-    if (buffer.mode == C.VIDEO_OUTPUT_MODE_SURFACE_YUV && !buffer.isDecodeOnly()) {
-      gav1ReleaseFrame(gav1DecoderContext, buffer);
+    if (outputBuffer.mode == C.VIDEO_OUTPUT_MODE_SURFACE_YUV && !outputBuffer.isDecodeOnly()) {
+      gav1ReleaseFrame(gav1DecoderContext, outputBuffer);
     }
-    super.releaseOutputBuffer(buffer);
+    super.releaseOutputBuffer(outputBuffer);
   }
 
   /**

libraries/decoder_vp9/src/main/java/androidx/media3/decoder/vp9/VpxDecoder.java

@@ -101,13 +101,13 @@ public final class VpxDecoder
   }
 
   @Override
-  protected void releaseOutputBuffer(VideoDecoderOutputBuffer buffer) {
+  protected void releaseOutputBuffer(VideoDecoderOutputBuffer outputBuffer) {
     // Decode only frames do not acquire a reference on the internal decoder buffer and thus do not
     // require a call to vpxReleaseFrame.
-    if (outputMode == C.VIDEO_OUTPUT_MODE_SURFACE_YUV && !buffer.isDecodeOnly()) {
-      vpxReleaseFrame(vpxDecContext, buffer);
+    if (outputMode == C.VIDEO_OUTPUT_MODE_SURFACE_YUV && !outputBuffer.isDecodeOnly()) {
+      vpxReleaseFrame(vpxDecContext, outputBuffer);
     }
-    super.releaseOutputBuffer(buffer);
+    super.releaseOutputBuffer(outputBuffer);
   }
 
   @Override