am d2bec096: Merge "NullPointerException in SQLiteSession"

# By László Dávid
# Via Gerrit Code Review (1) and László Dávid (1)
* commit 'd2bec0960d04578182905b34795c6895760944dd':
  NullPointerException in SQLiteSession

core/java/android/database/sqlite/SQLiteSession.java

@@ -926,7 +926,7 @@ public final class SQLiteSession {
     }
 
     private void throwIfNestedTransaction() {
-        if (mTransactionStack == null && mTransactionStack.mParent != null) {
+        if (hasNestedTransaction()) {
             throw new IllegalStateException("Cannot perform this operation because "
                     + "a nested transaction is in progress.");
         }