Deactivated the intelligibility enhancement functionality by default

webrtc/modules/audio_processing/BUILD.gn

Index: webrtc/modules/audio_processing/BUILD.gn
diff --git a/webrtc/modules/audio_processing/BUILD.gn b/webrtc/modules/audio_processing/BUILD.gn
index 0a8c5fc5a8903e2dade1fc94bf9b0ccd9899f1bb..ad9e16701e6b0792854e773947325087b645c0c4 100644
--- a/webrtc/modules/audio_processing/BUILD.gn
+++ b/webrtc/modules/audio_processing/BUILD.gn
@@ -18,6 +18,9 @@ declare_args() {
   # values the AEC receives. The corresponding define is set appropriately
   # in the code, but it can be force-enabled here for testing.
   aec_untrusted_delay_for_testing = false
+
+  # Chooses whether the intelligibility enhancer should be used.
+  intelligibility_enhancer = false
 }
 
 source_set("audio_processing") {
@@ -74,10 +77,6 @@ source_set("audio_processing") {
     "high_pass_filter_impl.cc",
     "high_pass_filter_impl.h",
     "include/audio_processing.h",
-    "intelligibility/intelligibility_enhancer.cc",
-    "intelligibility/intelligibility_enhancer.h",
-    "intelligibility/intelligibility_utils.cc",
-    "intelligibility/intelligibility_utils.h",
     "level_controller/biquad_filter.cc",
     "level_controller/biquad_filter.h",
     "level_controller/down_sampler.cc",
@@ -182,6 +181,18 @@ source_set("audio_processing") {
     deps += [ ":audioproc_debug_proto" ]
   }
 
+  if (intelligibility_enhancer) {
+    defines += [ "WEBRTC_INTELLIGIBILITY_ENHANCER=1" ]
+    sources += [
+      "intelligibility/intelligibility_enhancer.cc",
+      "intelligibility/intelligibility_enhancer.h",
+      "intelligibility/intelligibility_utils.cc",
+      "intelligibility/intelligibility_utils.h",
+    ]
+  } else {
+    defines += [ "WEBRTC_INTELLIGIBILITY_ENHANCER=0" ]
+  }
+
   if (rtc_prefer_fixed_point) {
     defines += [ "WEBRTC_NS_FIXED" ]
     sources += [