Added memory pressure monitor for linux.

base/memory/memory_pressure_monitor_chromeos_unittest.cc

Index: base/memory/memory_pressure_monitor_chromeos_unittest.cc
diff --git a/base/memory/memory_pressure_monitor_chromeos_unittest.cc b/base/memory/memory_pressure_monitor_chromeos_unittest.cc
index e0afa448a412e80a24be8293716ecd403d954de9..5666625d1b28eef3da4af62134e6df4399864b91 100644
--- a/base/memory/memory_pressure_monitor_chromeos_unittest.cc
+++ b/base/memory/memory_pressure_monitor_chromeos_unittest.cc
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "base/memory/memory_pressure_monitor_chromeos.h"
+#include "base/memory/memory_pressure_monitor.h"
 
 #include "base/basictypes.h"
 #include "base/memory/memory_pressure_listener.h"
@@ -10,7 +10,6 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace base {
-namespace chromeos {
 
 namespace {
 
@@ -162,5 +161,4 @@ TEST(ChromeOSMemoryPressureMonitorTest, CheckMemoryPressure) {
   EXPECT_EQ(j, i);
 }
 
-}  // namespace chromeos
 }  // namespace base