cros: Added a new function to quick unlock api for checking unfinished pins.

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 d4a75a4a9c1f5d7099287f350142e4b631f1bd45..e522360d22da3827bdb3c6c7177cc2a1b268daf7 100644
--- a/chrome/common/pref_names.cc
+++ b/chrome/common/pref_names.cc
@@ -924,6 +924,12 @@ const char kQuickUnlockModeWhitelist[] = "quick_unlock_mode_whitelist";
 // 2 - day. Users will have to enter their password every day.
 // 3 - week. Users will have to enter their password every week.
 const char kQuickUnlockTimeout[] = "quick_unlock_timeout";
+// Integer prefs indicating the minimum and maximum lengths of the lock screen
+// pin.
+const char kPinUnlockMinimumLength[] = "pin_unlock_minimum_length";
+const char kPinUnlockMaximumLength[] = "pin_unlock_maximum_length";
+// Boolean pref indicating whether users are allowed to set easy pins.
+const char kPinUnlockAllowWeakPins[] = "pin_unlock_allow_weak_pins";
 #endif  // defined(OS_CHROMEOS)
 
 // A boolean pref set to true if a Home button to open the Home pages should be