Fix potential crash

Author: SpongeBobSun

app/src/main/java/sun/bob/leela/runnable/QuickPassRunnable.java

@@ -44,6 +44,11 @@ public QuickPassRunnable(String quickCode, String password) {
 
     private void getPasswordHash() {
         Account account = AccountHelper.getInstance(null).getQuickAccount();
+        if (this.passwordHash == null) {
+            UserDefault.getInstance(null).clearQuickPassword();
+            AccountHelper.getInstance(null).clearQuickAccount();
+            return;
+        }
         this.passwordHash = account.getHash();
     }