chromeos: Switch --first-boot to --first-exec-after-boot.

chromeos/chromeos_switches.cc

Index: chromeos/chromeos_switches.cc
diff --git a/chromeos/chromeos_switches.cc b/chromeos/chromeos_switches.cc
index 0d8b5a239dc5496240091d398c78a08e30955d55..8577279d54ec2fc535ff7aa5c584b230be9ca927 100644
--- a/chromeos/chromeos_switches.cc
+++ b/chromeos/chromeos_switches.cc
@@ -120,8 +120,9 @@ const char kFileManagerShowCheckboxes[]     = "file-manager-show-checkboxes";
 const char kFileManagerEnableWebstoreIntegration[] =
     "file-manager-enable-webstore-integration";
 
-// Passed to Chrome on first boot. Not passed on restart after sign out.
-const char kFirstBoot[]                     = "first-boot";
+// Passed to Chrome the first time that it's run after the system boots.
+// Not passed on restart after sign out.
+const char kFirstExecAfterBoot[]            = "first-exec-after-boot";
 
 // Usually in browser tests the usual login manager bringup is skipped so that
 // tests can change how it's brought up. This flag disables that.