Revert of Reland: Lazily initialize MessageLoop for faster thread startup

base/message_loop/message_pump_perftest.cc

Index: base/message_loop/message_pump_perftest.cc
diff --git a/base/message_loop/message_pump_perftest.cc b/base/message_loop/message_pump_perftest.cc
index 0bf3d0ca9421ff865eff73d0a125e91e0a10a261..b3e5604c8133a4576b872861b1a67b6e8595bb36 100644
--- a/base/message_loop/message_pump_perftest.cc
+++ b/base/message_loop/message_pump_perftest.cc
@@ -20,6 +20,7 @@
 #endif
 
 namespace base {
+namespace {
 
 class ScheduleWorkTest : public testing::Test {
  public:
@@ -222,6 +223,9 @@
   ScheduleWork(MessageLoop::TYPE_JAVA, 4);
 }
 #endif
+
+static void DoNothing() {
+}
 
 class FakeMessagePump : public MessagePump {
  public:
@@ -285,4 +289,5 @@
   Run(1000, 100);
 }
 
+}  // namespace
 }  // namespace base