diff --git a/media/ndk/include/media/NdkMediaFormat.h b/media/ndk/include/media/NdkMediaFormat.h
index dd39acf..778f9c2 100644
--- a/media/ndk/include/media/NdkMediaFormat.h
+++ b/media/ndk/include/media/NdkMediaFormat.h
@@ -88,70 +88,70 @@
 /**
  * XXX should these be ints/enums that we look up in a table as needed?
  */
-extern const char* AMEDIAFORMAT_KEY_AAC_DRC_ATTENUATION_FACTOR;
-extern const char* AMEDIAFORMAT_KEY_AAC_DRC_BOOST_FACTOR;
-extern const char* AMEDIAFORMAT_KEY_AAC_DRC_HEAVY_COMPRESSION;
-extern const char* AMEDIAFORMAT_KEY_AAC_DRC_TARGET_REFERENCE_LEVEL;
-extern const char* AMEDIAFORMAT_KEY_AAC_ENCODED_TARGET_LEVEL;
-extern const char* AMEDIAFORMAT_KEY_AAC_MAX_OUTPUT_CHANNEL_COUNT;
+extern const char* AMEDIAFORMAT_KEY_AAC_DRC_ATTENUATION_FACTOR __INTRODUCED_IN(28);
+extern const char* AMEDIAFORMAT_KEY_AAC_DRC_BOOST_FACTOR __INTRODUCED_IN(28);
+extern const char* AMEDIAFORMAT_KEY_AAC_DRC_HEAVY_COMPRESSION __INTRODUCED_IN(28);
+extern const char* AMEDIAFORMAT_KEY_AAC_DRC_TARGET_REFERENCE_LEVEL __INTRODUCED_IN(28);
+extern const char* AMEDIAFORMAT_KEY_AAC_ENCODED_TARGET_LEVEL __INTRODUCED_IN(28);
+extern const char* AMEDIAFORMAT_KEY_AAC_MAX_OUTPUT_CHANNEL_COUNT __INTRODUCED_IN(28);
 extern const char* AMEDIAFORMAT_KEY_AAC_PROFILE;
-extern const char* AMEDIAFORMAT_KEY_AAC_SBR_MODE;
-extern const char* AMEDIAFORMAT_KEY_AUDIO_SESSION_ID;
-extern const char* AMEDIAFORMAT_KEY_BITRATE_MODE;
+extern const char* AMEDIAFORMAT_KEY_AAC_SBR_MODE __INTRODUCED_IN(28);
+extern const char* AMEDIAFORMAT_KEY_AUDIO_SESSION_ID __INTRODUCED_IN(28);
+extern const char* AMEDIAFORMAT_KEY_BITRATE_MODE __INTRODUCED_IN(28);
 extern const char* AMEDIAFORMAT_KEY_BIT_RATE;
-extern const char* AMEDIAFORMAT_KEY_CAPTURE_RATE;
+extern const char* AMEDIAFORMAT_KEY_CAPTURE_RATE __INTRODUCED_IN(28);
 extern const char* AMEDIAFORMAT_KEY_CHANNEL_COUNT;
 extern const char* AMEDIAFORMAT_KEY_CHANNEL_MASK;
 extern const char* AMEDIAFORMAT_KEY_COLOR_FORMAT;
-extern const char* AMEDIAFORMAT_KEY_COLOR_RANGE;
-extern const char* AMEDIAFORMAT_KEY_COLOR_STANDARD;
-extern const char* AMEDIAFORMAT_KEY_COLOR_TRANSFER;
-extern const char* AMEDIAFORMAT_KEY_COMPLEXITY;
+extern const char* AMEDIAFORMAT_KEY_COLOR_RANGE __INTRODUCED_IN(28);
+extern const char* AMEDIAFORMAT_KEY_COLOR_STANDARD __INTRODUCED_IN(28);
+extern const char* AMEDIAFORMAT_KEY_COLOR_TRANSFER __INTRODUCED_IN(28);
+extern const char* AMEDIAFORMAT_KEY_COMPLEXITY __INTRODUCED_IN(28);
 extern const char* AMEDIAFORMAT_KEY_CSD;
 extern const char* AMEDIAFORMAT_KEY_CSD_0;
 extern const char* AMEDIAFORMAT_KEY_CSD_1;
 extern const char* AMEDIAFORMAT_KEY_CSD_2;
-extern const char* AMEDIAFORMAT_KEY_DISPLAY_CROP;
+extern const char* AMEDIAFORMAT_KEY_DISPLAY_CROP __INTRODUCED_IN(28);
 extern const char* AMEDIAFORMAT_KEY_DISPLAY_HEIGHT;
 extern const char* AMEDIAFORMAT_KEY_DISPLAY_WIDTH;
 extern const char* AMEDIAFORMAT_KEY_DURATION;
 extern const char* AMEDIAFORMAT_KEY_FLAC_COMPRESSION_LEVEL;
 extern const char* AMEDIAFORMAT_KEY_FRAME_RATE;
-extern const char* AMEDIAFORMAT_KEY_GRID_COLUMNS;
-extern const char* AMEDIAFORMAT_KEY_GRID_ROWS;
+extern const char* AMEDIAFORMAT_KEY_GRID_COLUMNS __INTRODUCED_IN(28);
+extern const char* AMEDIAFORMAT_KEY_GRID_ROWS __INTRODUCED_IN(28);
 extern const char* AMEDIAFORMAT_KEY_HDR_STATIC_INFO;
 extern const char* AMEDIAFORMAT_KEY_HEIGHT;
-extern const char* AMEDIAFORMAT_KEY_INTRA_REFRESH_PERIOD;
+extern const char* AMEDIAFORMAT_KEY_INTRA_REFRESH_PERIOD __INTRODUCED_IN(28);
 extern const char* AMEDIAFORMAT_KEY_IS_ADTS;
 extern const char* AMEDIAFORMAT_KEY_IS_AUTOSELECT;
 extern const char* AMEDIAFORMAT_KEY_IS_DEFAULT;
 extern const char* AMEDIAFORMAT_KEY_IS_FORCED_SUBTITLE;
 extern const char* AMEDIAFORMAT_KEY_I_FRAME_INTERVAL;
 extern const char* AMEDIAFORMAT_KEY_LANGUAGE;
-extern const char* AMEDIAFORMAT_KEY_LATENCY;
-extern const char* AMEDIAFORMAT_KEY_LEVEL;
+extern const char* AMEDIAFORMAT_KEY_LATENCY __INTRODUCED_IN(28);
+extern const char* AMEDIAFORMAT_KEY_LEVEL __INTRODUCED_IN(28);
 extern const char* AMEDIAFORMAT_KEY_MAX_HEIGHT;
 extern const char* AMEDIAFORMAT_KEY_MAX_INPUT_SIZE;
 extern const char* AMEDIAFORMAT_KEY_MAX_WIDTH;
 extern const char* AMEDIAFORMAT_KEY_MIME;
 extern const char* AMEDIAFORMAT_KEY_MPEG_USER_DATA;
-extern const char* AMEDIAFORMAT_KEY_OPERATING_RATE;
-extern const char* AMEDIAFORMAT_KEY_PCM_ENCODING;
-extern const char* AMEDIAFORMAT_KEY_PRIORITY;
-extern const char* AMEDIAFORMAT_KEY_PROFILE;
+extern const char* AMEDIAFORMAT_KEY_OPERATING_RATE __INTRODUCED_IN(28);
+extern const char* AMEDIAFORMAT_KEY_PCM_ENCODING __INTRODUCED_IN(28);
+extern const char* AMEDIAFORMAT_KEY_PRIORITY __INTRODUCED_IN(28);
+extern const char* AMEDIAFORMAT_KEY_PROFILE __INTRODUCED_IN(28);
 extern const char* AMEDIAFORMAT_KEY_PUSH_BLANK_BUFFERS_ON_STOP;
 extern const char* AMEDIAFORMAT_KEY_REPEAT_PREVIOUS_FRAME_AFTER;
-extern const char* AMEDIAFORMAT_KEY_ROTATION;
+extern const char* AMEDIAFORMAT_KEY_ROTATION __INTRODUCED_IN(28);
 extern const char* AMEDIAFORMAT_KEY_SAMPLE_RATE;
 extern const char* AMEDIAFORMAT_KEY_SEI;
-extern const char* AMEDIAFORMAT_KEY_SLICE_HEIGHT;
+extern const char* AMEDIAFORMAT_KEY_SLICE_HEIGHT __INTRODUCED_IN(28);
 extern const char* AMEDIAFORMAT_KEY_STRIDE;
 extern const char* AMEDIAFORMAT_KEY_TEMPORAL_LAYER_ID;
-extern const char* AMEDIAFORMAT_KEY_TEMPORAL_LAYERING;
-extern const char* AMEDIAFORMAT_KEY_TILE_HEIGHT;
-extern const char* AMEDIAFORMAT_KEY_TILE_WIDTH;
+extern const char* AMEDIAFORMAT_KEY_TEMPORAL_LAYERING __INTRODUCED_IN(28);
+extern const char* AMEDIAFORMAT_KEY_TILE_HEIGHT __INTRODUCED_IN(28);
+extern const char* AMEDIAFORMAT_KEY_TILE_WIDTH __INTRODUCED_IN(28);
 extern const char* AMEDIAFORMAT_KEY_TIME_US;
-extern const char* AMEDIAFORMAT_KEY_TRACK_ID;
+extern const char* AMEDIAFORMAT_KEY_TRACK_ID __INTRODUCED_IN(28);
 extern const char* AMEDIAFORMAT_KEY_TRACK_INDEX;
 extern const char* AMEDIAFORMAT_KEY_WIDTH;