Add missing libs for the mac build.

WebRTC is trying to enable the support for the component build and
when is_component_build=true some Chromium targets fail to link because
they were relying on WebRTC to link with some .frameworks.

Bug: webrtc:9419
Change-Id: I064289025aa7eab7cb5008d9d9ae71a013119c65
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1865330
Reviewed-by: Nico Weber <[email protected]>
Reviewed-by: Jamie Walch <[email protected]>
Reviewed-by: Yuri Wiitala <[email protected]>
Commit-Queue: Mirko Bonadei <[email protected]>
Cr-Commit-Position: refs/heads/master@{#707123}
diff --git a/content/browser/BUILD.gn b/content/browser/BUILD.gn
index 0a1cdad..75ba868 100644
--- a/content/browser/BUILD.gn
+++ b/content/browser/BUILD.gn
@@ -2042,6 +2042,7 @@
   }
 
   if (is_mac) {
+    libs += [ "AppKit.framework" ]
     sources += [
       "../app_shim_remote_cocoa/web_contents_ns_view_bridge.h",
       "../app_shim_remote_cocoa/web_contents_ns_view_bridge.mm",