Fix errors found in Mac gn component builds

media/BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/android/config.gni")
 import("//build/config/arm.gni")
 import("//build/config/features.gni")
 import("//build/config/linux/pkg_config.gni")
 import("//build/config/ui.gni")
 import("//media/media_options.gni")
@@ skipping 664 matching lines @@
 
   if (is_mac || is_ios) {
     deps += [ "//media/base/mac" ]
   }
 
   if (is_mac) {
     sources += [
       "midi/midi_manager_mac_unittest.cc",
       "video/capture/mac/video_capture_device_factory_mac_unittest.mm",
     ]
+    libs = [
+      # Required by midi_manager_mac_unittest.cc.
+      "CoreMIDI.framework",
+    ]
   }
 
   if (use_alsa) {
     sources += [ "midi/midi_manager_alsa_unittest.cc" ]
   }
 
   #      include_dirs += [
   #        # Needed by media_drm_bridge.cc.
   #        target_gen_dir,
   #      ],
@@ skipping 90 matching lines @@
       "//media/base:test_support",
       "//media/test:pipeline_integration_tests",
       "//testing/gmock",
       "//testing/gtest",
       "//third_party/ffmpeg",
       "//ui/gfx/geometry",
       "//ui/gfx:test_support",
     ]
   }
 }