Add oom tab killing and the about:discards page on linux

chrome/common/chrome_switches.h

Index: chrome/common/chrome_switches.h
diff --git a/chrome/common/chrome_switches.h b/chrome/common/chrome_switches.h
index a3b53926b257fc1636d23f6d51ec38a72a6dc5e6..3494d3e812c3680ac0cb3851d28206e43caf664a 100644
--- a/chrome/common/chrome_switches.h
+++ b/chrome/common/chrome_switches.h
@@ -368,10 +368,13 @@ extern const char kMetricsClientID[];
 extern const char kRelauncherProcess[];
 #endif  // defined(OS_MACOSX)
 
+#if defined(OS_WIN) || defined(OS_LINUX)
+extern const char kEnableTabDiscarding[];
+#endif
+
 #if defined(OS_WIN)
 extern const char kEnableCloudPrintXps[];
 extern const char kEnableProfileShortcutManager[];
-extern const char kEnableTabDiscarding[];
 extern const char kForceDesktop[];
 extern const char kForceImmersive[];
 extern const char kHideIcons[];