Revert "NdkMediaExtractor: per-sample format metadata API"

This reverts commit 062ffd042fcbd237f445d499bc8ea8c5baf61d98.

Bug: 63934228
Bug: 74089496

Reason for revert: original change bypassed presubmit, causing mediaextractor crash, 

Change-Id: Iac4c49659dfa7415908d60da98a2285c583a1196
diff --git a/media/libmediaplayer2/nuplayer2/NuPlayer2.cpp b/media/libmediaplayer2/nuplayer2/NuPlayer2.cpp
index 060b698..5971a8b 100644
--- a/media/libmediaplayer2/nuplayer2/NuPlayer2.cpp
+++ b/media/libmediaplayer2/nuplayer2/NuPlayer2.cpp
@@ -2842,7 +2842,7 @@
 void NuPlayer2::sendSubtitleData(const sp<ABuffer> &buffer, int32_t baseIndex) {
     int32_t trackIndex;
     int64_t timeUs, durationUs;
-    CHECK(buffer->meta()->findInt32(AMEDIAFORMAT_KEY_TRACK_INDEX, &trackIndex));
+    CHECK(buffer->meta()->findInt32("trackIndex", &trackIndex));
     CHECK(buffer->meta()->findInt64("timeUs", &timeUs));
     CHECK(buffer->meta()->findInt64("durationUs", &durationUs));