Delete unused empty build target audio_jni

Bug: webrtc:369904700
Change-Id: Icb1a3ce129a8cc5004ff1683f347dd82699bc48c
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/388600
Reviewed-by: Sergey Silkin <ssilkin@webrtc.org>
Commit-Queue: Sergey Silkin <ssilkin@webrtc.org>
Auto-Submit: Danil Chapovalov <danilchap@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#44460}
diff --git a/sdk/android/BUILD.gn b/sdk/android/BUILD.gn
index b1e8293..6d8992f 100644
--- a/sdk/android/BUILD.gn
+++ b/sdk/android/BUILD.gn
@@ -616,14 +616,6 @@
     ]
   }
 
-  # TODO: bugs.webrtc.org/369904700 - Delete when downstream dependencies stop
-  # depending on this now empty target.
-  rtc_source_set("audio_jni") {
-    visibility = [ "*" ]
-    sources = []
-    deps = []
-  }
-
   rtc_library("builtin_audio_codecs_jni") {
     visibility = [ "*" ]
     allow_poison = [ "audio_codecs" ]