Decoupling rtc_base from apple specific code [without cyclic deps]

webrtc/modules/BUILD.gn

Index: webrtc/modules/BUILD.gn
diff --git a/webrtc/modules/BUILD.gn b/webrtc/modules/BUILD.gn
index 94e2d4fa5333b8eed988ce81b79cde5d801ea9f9..f08ea24539240ce62d5865b8ec5f0c53ba43f87c 100644
--- a/webrtc/modules/BUILD.gn
+++ b/webrtc/modules/BUILD.gn
@@ -84,6 +84,10 @@ if (rtc_include_tests) {
       deps += [ ":modules_tests_bundle_data" ]
     }
 
+    if (is_ios || is_mac) {
+      deps += [ "../rtc_base:rtc_base_apple" ]
+    }
+
     if (!build_with_chromium && is_clang) {
       # Suppress warnings from the Chromium Clang plugin (bugs.webrtc.org/163).
       suppressed_configs += [ "//build/config/clang:find_bad_constructs" ]
@@ -256,5 +260,8 @@ if (rtc_include_tests) {
       configs += [ "..:common_objc" ]
       ldflags = [ "-ObjC" ]
     }
+    if (is_ios || is_mac) {
+      deps += [ "../rtc_base:rtc_base_apple" ]
+    }
   }
 }