Compile rtc_base_objc and rtc_api_objc for Mac

webrtc/api/api_tests.gyp

Index: webrtc/api/api_tests.gyp
diff --git a/webrtc/api/api_tests.gyp b/webrtc/api/api_tests.gyp
index 5af1cabfebafcb43664b7f61c7f98b5897a31ca6..09173410086b29e8eab44b5b941a554c7819ad46 100644
--- a/webrtc/api/api_tests.gyp
+++ b/webrtc/api/api_tests.gyp
@@ -137,11 +137,12 @@
         },
       ],  # targets
     }],  # OS=="android"
-    ['OS=="ios"', {
+    ['OS=="ios" or OS=="mac"', {
       'targets': [
         {
           'target_name': 'rtc_api_objc_tests',
           'type': 'executable',
+          'includes': [ '../build/objc_common.gypi' ],
           'dependencies': [
             '<(webrtc_root)/api/api.gyp:rtc_api_objc',
             '<(webrtc_root)/base/base_tests.gyp:rtc_base_tests_utils',
@@ -155,9 +156,6 @@
             'objctests/RTCSessionDescriptionTest.mm',
           ],
           'xcode_settings': {
-            'CLANG_ENABLE_OBJC_ARC': 'YES',
-            'CLANG_WARN_OBJC_MISSING_PROPERTY_SYNTHESIS': 'YES',
-            'GCC_PREFIX_HEADER': 'objc/WebRTC-Prefix.pch',
             # |-ObjC| flag needed to make sure category method implementations
             # are included:
             # https://developer.apple.com/library/mac/qa/qa1490/_index.html
@@ -165,7 +163,7 @@
           },
         },
       ],
-    }],  # OS=="ios"
+    }],  # OS=="ios" or OS=="mac"
     ['OS=="android"', {
       'targets': [
         {