I used the method below which really is a conundrum of all the ones above. I also found that onOptionsItemSelected is never activated.
mDrawerToggle.setDrawerIndicatorEnabled(false);
getSupportActionBar().setHomeButtonEnabled(true);
Toolbar toolbar = (Toolbar) findViewById(R.id.tool_bar);
if (toolbar != null) {
toolbar.setNavigationOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
onBackPressed();
}
});
}