Moved audioproc_f interface into api directory.

The interface of the audioproc_f tool should be located in the api/ directory, so it becomes visible to the outside world.

Bug: webrtc:8732
Change-Id: Ia7475883aeb0e1f7a6afa5e791204b38dc53a8b8
Reviewed-on: https://webrtc-review.googlesource.com/61801
Commit-Queue: Ivo Creusen <ivoc@webrtc.org>
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22449}
diff --git a/api/BUILD.gn b/api/BUILD.gn
index a238357..ec71784 100644
--- a/api/BUILD.gn
+++ b/api/BUILD.gn
@@ -313,6 +313,22 @@
 }
 
 if (rtc_include_tests) {
+  if (rtc_enable_protobuf) {
+    rtc_source_set("audioproc_f_api") {
+      visibility = [ "*" ]
+      testonly = true
+      sources = [
+        "test/audioproc_float.cc",
+        "test/audioproc_float.h",
+      ]
+
+      deps = [
+        "../modules/audio_processing:audio_processing",
+        "../modules/audio_processing:audioproc_f_impl",
+      ]
+    }
+  }
+
   rtc_source_set("mock_audio_mixer") {
     testonly = true
     sources = [