Enable Mojo on iOS.

mojo/embedder/embedder_unittest.cc

Index: mojo/embedder/embedder_unittest.cc
diff --git a/mojo/embedder/embedder_unittest.cc b/mojo/embedder/embedder_unittest.cc
index be663fd92bca9117b44e19a49ce24d7a1d46b328..aa8138a705b9cead0cc86ca39f5622aa49de62e2 100644
--- a/mojo/embedder/embedder_unittest.cc
+++ b/mojo/embedder/embedder_unittest.cc
@@ -294,6 +294,9 @@ TEST_F(EmbedderTest, ChannelsHandlePassing) {
 //  10.                          (close)
 //  11.                                      (wait/cl.)
 //  12.                                                  (wait/cl.)
+
+// The multiprocess unittests don't build (and are not relevant) on iOS.
+#if 0
 TEST_F(EmbedderTest, MultiprocessChannels) {
   Init();
   mojo::test::MultiprocessTestHelper multiprocess_test_helper;
@@ -501,6 +504,7 @@ MOJO_MULTIPROCESS_TEST_CHILD_TEST(MultiprocessChannelsClient) {
 
   EXPECT_TRUE(test::Shutdown());
 }
+#endif
 
 // TODO(vtl): Test immediate write & close.
 // TODO(vtl): Test broken-connection cases.