Stop linking in the old Mojo EDK.

mojo/edk/test/multiprocess_test_helper.h

Index: mojo/edk/test/multiprocess_test_helper.h
diff --git a/mojo/edk/test/multiprocess_test_helper.h b/mojo/edk/test/multiprocess_test_helper.h
index 55fef7c73ad1fa80f36a2186839aa1d3f7dac9bd..be73734cbf82f97a55125b3d70d16ea5f9854129 100644
--- a/mojo/edk/test/multiprocess_test_helper.h
+++ b/mojo/edk/test/multiprocess_test_helper.h
@@ -23,6 +23,8 @@ namespace test {
 
 extern const char kBrokerHandleSwitch[];
 
+#if !defined(OS_IOS)
+
 class MultiprocessTestHelper {
  public:
   MultiprocessTestHelper();
@@ -97,6 +99,8 @@ class MultiprocessTestHelper {
   }                                                        \
   void test_child_name##TestChildTest()
 
+#endif  // !defined(OS_IOS)
+
 }  // namespace test
 }  // namespace edk
 }  // namespace mojo