Move IPC tests into anonymous namespaces.

ipc/ipc_channel_posix_unittest.cc

Index: ipc/ipc_channel_posix_unittest.cc
diff --git a/ipc/ipc_channel_posix_unittest.cc b/ipc/ipc_channel_posix_unittest.cc
index 0484f078069bd349915ec724c8c533e32cfc6d4b..56549f15193546c427b562813c10a4f61f30dadc 100644
--- a/ipc/ipc_channel_posix_unittest.cc
+++ b/ipc/ipc_channel_posix_unittest.cc
@@ -92,8 +92,6 @@ class IPCChannelPosixTestListener : public IPC::Listener {
   bool quit_only_on_message_;
 };
 
-}  // namespace
-
 class IPCChannelPosixTest : public base::MultiProcessTest {
  public:
   static void SetUpSocket(IPC::ChannelHandle *handle,
@@ -425,3 +423,5 @@ MULTIPROCESS_TEST_MAIN(IPCChannelPosixFailConnectionProc) {
   }
   return 0;
 }
+
+}  // namespace