Could you extend the test to check that all methods works correctly with sparse input?

```
Methods
decision_function(X)	Compute the decision function of X.
predict_log_proba(X)	Predict class log-probabilities for X.
predict_proba(X)	Predict class probabilities for X.
score(X, y[, sample_weight])	Returns the mean accuracy on the given test data and labels.
staged_decision_function(X)	Compute decision function of X for each boosting iteration.
staged_predict(X)	Return staged predictions for X.
staged_predict_proba(X)	Predict class probabilities for X.
staged_score(X, y[, sample_weight])	Return staged scores for X, y.
```