Add missing dependencies on audio, video and call to the new GN files.

This caused linker failures when depending on the new `api` target.

TBR=henrika@webrtc.org
NOTRY=True

Review-Url: https://codereview.webrtc.org/2029323006
Cr-Commit-Position: refs/heads/master@{#13042}
diff --git a/webrtc/api/BUILD.gn b/webrtc/api/BUILD.gn
index f84010d..b7d87ef 100644
--- a/webrtc/api/BUILD.gn
+++ b/webrtc/api/BUILD.gn
@@ -117,6 +117,7 @@
   }
 
   deps = [
+    "../call",
     "../media",
     "../pc",
   ]