Add a flag to specify whether to show ARC Files app in launcher.

chromeos/chromeos_switches.cc

Index: chromeos/chromeos_switches.cc
diff --git a/chromeos/chromeos_switches.cc b/chromeos/chromeos_switches.cc
index 9e04b6d029ac2fff1d0efbd8bf8e06a6dfdd7818..7498ad6cf786135b8ae1cb42a8a1b33346040c18 100644
--- a/chromeos/chromeos_switches.cc
+++ b/chromeos/chromeos_switches.cc
@@ -399,6 +399,9 @@ const char kPowerStub[] = "power-stub";
 //  'interactive=3' - Interactive mode, connect/scan/etc requests take 3 secs
 const char kShillStub[] = "shill-stub";
 
+// Specifies whether we show ARC version of Files app in Chrome app launcher.
+const char kShowArcFilesApp[] = "show-arc-files-app";
+
 // Sends test messages on first call to RequestUpdate (stub only).
 const char kSmsTestMessages[] = "sms-test-messages";