Files.app: Relax condtion to skip OOBE demo mode.

Due to Issue 398271 , we are disabling OOBE demo on test image, which makes it
hard to test OOBE demo. We can relax the condition, so that it does not skip
when derelict related switches are specified.

BUG=485471
TEST=None

Review URL: https://codereview.chromium.org/1130173002

Cr-Commit-Position: refs/heads/master@{#329339}

chrome/browser/ui/webui/chromeos/login/demo_mode_detector.cc

@@ -39,7 +39,13 @@ void DemoModeDetector::InitDetection() {
           switches::kDisableDemoMode))
     return;
 
-  if (base::SysInfo::IsRunningOnChromeOS()) {
+  const bool has_derelict_switch =
+      base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kDerelictDetectionTimeout) ||
+      base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kDerelictIdleTimeout);
+
+  if (base::SysInfo::IsRunningOnChromeOS() && !has_derelict_switch) {
     std::string track;
     // We're running on an actual device; if we cannot find our release track
     // value or if the track contains "testimage", don't start demo mode.