ADM unit test now runs on Mac and Windows as well.

TBR=solenberg
BUG=webrtc:7273

Review-Url: https://codereview.webrtc.org/2783863002
Cr-Commit-Position: refs/heads/master@{#17451}
diff --git a/webrtc/modules/audio_device/BUILD.gn b/webrtc/modules/audio_device/BUILD.gn
index 629de99..9c776d3 100644
--- a/webrtc/modules/audio_device/BUILD.gn
+++ b/webrtc/modules/audio_device/BUILD.gn
@@ -275,7 +275,7 @@
       "../utility:utility",
       "//testing/gmock",
     ]
-    if (is_linux) {
+    if (is_linux || is_mac || is_win) {
       sources += [ "audio_device_unittest.cc" ]
     }
     if (is_android) {