Leaving all original files in talk/app/webrtc/objc until we can officially tell clients about the new locations.

Also changes presubmit script to not run cpplint on objc dirs.

BUG=

Review URL: https://codereview.webrtc.org/1467173006

Cr-Commit-Position: refs/heads/master@{#10815}

webrtc/base/base.gyp

@@ -22,6 +22,27 @@
         }],
       ],
     }],
+    # TODO(tkchin): Mac support. There are a bunch of problems right now because
+    # of some settings pulled down from Chromium.
+    ['OS=="ios"', {
+      'targets': [
+        {
+          'target_name': 'rtc_base_objc',
+          'type': 'static_library',
+          'dependencies': [
+            'rtc_base',
+          ],
+          'sources': [
+            'objc/RTCLogging.h',
+            'objc/RTCLogging.mm'
+          ],
+          'xcode_settings': {
+            'CLANG_ENABLE_OBJC_ARC': 'YES',
+            'CLANG_WARN_OBJC_MISSING_PROPERTY_SYNTHESIS': 'YES',
+          },
+        }
+      ],
+    }], # OS=="ios"
   ],
   'targets': [
     {