Exclude ephemeral-guest-profiles from Chrome OS.

The feature is not for Chrome OS. Remove it from Chrome OS.
This is also for the preparation to unset OS_LINUX for Chrome OS build.
With this CL, the part will not be affected on switching.

Bug: 1110266
Test: Built locally.
Change-Id: Ia22a2dff5cc82e223559abc11e76171c739f03dc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2452030
Commit-Queue: Hidehiko Abe <[email protected]>
Auto-Submit: Hidehiko Abe <[email protected]>
Reviewed-by: Lei Zhang <[email protected]>
Reviewed-by: Ramin Halavati <[email protected]>
Cr-Commit-Position: refs/heads/master@{#815073}
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index 439c65d..00f45be1 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -6554,13 +6554,15 @@
      FEATURE_VALUE_TYPE(features::kMuteNotificationsDuringScreenShare)},
 #endif  // !defined(OS_ANDROID)
 
-#if defined(OS_WIN) || defined(OS_LINUX) || defined(OS_MAC)
+#if defined(OS_WIN) || (defined(OS_LINUX) && !defined(OS_CHROMEOS)) || \
+    defined(OS_MAC)
     {"enable-ephemeral-guest-profiles-on-desktop",
      flag_descriptions::kEnableEphemeralGuestProfilesOnDesktopName,
      flag_descriptions::kEnableEphemeralGuestProfilesOnDesktopDescription,
      kOsWin | kOsLinux | kOsMac,
      FEATURE_VALUE_TYPE(features::kEnableEphemeralGuestProfilesOnDesktop)},
-#endif  // defined(OS_WIN) || defined(OS_LINUX) || defined(OS_MAC)
+#endif  // defined(OS_WIN) || (defined(OS_LINUX) && !defined(OS_CHROMEOS)) ||
+        // defined(OS_MAC)
 
 #if defined(OS_ANDROID)
     {"decouple-sync-from-android-auto-sync",