Make tcp_client_socket_unittest pass on Linux....

base/message_loop.cc

Index: base/message_loop.cc
===================================================================
--- base/message_loop.cc	(revision 2108)
+++ base/message_loop.cc	(working copy)
@@ -13,6 +13,10 @@
 #include "base/string_util.h"
 #include "base/thread_local.h"
 
+#if defined(OS_LINUX)
+#include "base/message_pump_libevent.h"
+#endif
+
 // A lazily created thread local storage for quick access to a thread's message
 // loop, if one exists.  This should be safe and free of static constructors.
 static base::LazyInstance<base::ThreadLocalPointer<MessageLoop> > lazy_tls_ptr(
@@ -78,6 +82,12 @@
   } else {
     pump_ = new base::MessagePumpWin();
   }
+#elif defined(OS_LINUX)
+  if (type_ == TYPE_IO) {
+    pump_ = new base::MessagePumpLibevent();
+  } else {
+    pump_ = new base::MessagePumpDefault();
+  }
 #else
   pump_ = new base::MessagePumpDefault();
 #endif