arc: Make request to remove Android's data folder persistent.

chrome/common/pref_names.cc

Index: chrome/common/pref_names.cc
diff --git a/chrome/common/pref_names.cc b/chrome/common/pref_names.cc
index e7c71f438e4fd227de75ebd2aa16220719594247..f16b2a68c3e1c5f4b12d42f1d2b4630becc276e0 100644
--- a/chrome/common/pref_names.cc
+++ b/chrome/common/pref_names.cc
@@ -22,6 +22,8 @@ namespace prefs {
 const char kArcApps[] = "arc.apps";
 // A preference to store backup and restore state for Android apps.
 const char kArcBackupRestoreEnabled[] = "arc.backup_restore.enabled";
+// A preference to indicate that Android's data directory should be removed.
+const char kArcDataRemoveRequested[] = "arc.data.remove_requested";
 // A preference to keep Android apps enabled state.
 const char kArcEnabled[] = "arc.enabled";
 // A preference that indicated whether Android reported that it's compliant