GN: Add SDK tests to rtc_unittests.

webrtc/base/BUILD.gn

Index: webrtc/base/BUILD.gn
diff --git a/webrtc/base/BUILD.gn b/webrtc/base/BUILD.gn
index 7d2035db862e81b8b3d7cb3462719f7efe99acef..1fffbe858737ebb3cd95c32371c5903c66d3860f 100644
--- a/webrtc/base/BUILD.gn
+++ b/webrtc/base/BUILD.gn
@@ -49,7 +49,7 @@ config("rtc_base_all_dependent_config") {
       #"Foundation.framework",  # Already in //build/config:default_libs.
       "Security.framework",
       "SystemConfiguration.framework",
-      "UIKit.framework",  # Already in //build/config:default_libs.
+      "UIKit.framework",

[tkchin_webrtc, 2016/06/07 22:14:54]

I feel like this isn't the best place to add these libs. Shouldn't the targets
that require them be the ones that specify them? But this is indeed the path of
least resistance because it would take a lot of time to track down which libs
require them.

[kjellander_webrtc, 2016/06/08 08:03:21]

You're absolutely right, but I don't want to involve cleanup in this effort -
focus is on getting us over to GN first. Then we can iterate a lot faster with
such cleanups.

     ]
   }
   if (is_mac) {
@@ -61,7 +61,7 @@ config("rtc_base_all_dependent_config") {
       "SystemConfiguration.framework",
     ]
     if (current_cpu == "x86") {
-      libs = [ "Carbon.framework" ]  # Already in //build/config:default_libs.
+      libs = [ "Carbon.framework" ]

[Nico, 2016/06/13 11:32:34]

This must be +=, not =, else gn will fail with "this overwrites a non-empty
list" when configuring a 32-bit build. Can you add a + here please?

(i'd do it myself, but editing webrtc as part of a chromium checkout and running
`git cl upload` there doesn't work, while it works fine for all other
third-party chromium deps. I do have a standalone webrtc checkout, but it's
still on webrtc, and getting a fresh standalone webrtc checkout will take hours
and I'm on a laptop and traveling…)

     }
   }
 }
@@ -558,7 +558,13 @@ static_library("rtc_base") {
       "macutils.cc",
       "macutils.h",
     ]
-    libs += [ "CoreServices.framework" ]  # For GetGestalt in macutils.cc.
+    libs += [
+      # For ProcessInformationCopyDictionary in unixfilesystem.cc.
+      "ApplicationServices.framework",
+
+      # For GetGestalt in macutils.cc.
+      "CoreServices.framework",
+    ]
   }
 
   if (is_win) {