Create ash memory monitor

ash/ash_switches.cc

Index: ash/ash_switches.cc
diff --git a/ash/ash_switches.cc b/ash/ash_switches.cc
index 6094cf0adf3dca90f89ead8291984ac42f5e1264..1b0b24b793789ed0d47e64e12a83eaee71a38fb8 100644
--- a/ash/ash_switches.cc
+++ b/ash/ash_switches.cc
@@ -38,6 +38,11 @@ const char kAshDisablePanelFitting[] = "ash-disable-panel-fitting";
 // Enable advanced gestures (e.g. for window management).
 const char kAshEnableAdvancedGestures[] = "ash-enable-advanced-gestures";
 
+#if defined(OS_LINUX)
+// Enable memory monitoring.
+const char kAshEnableMemoryMonitor[] = "ash-enable-memory-monitor";
+#endif
+
 // Enables the Oak tree viewer.
 const char kAshEnableOak[] = "ash-enable-oak";