There's a minor change to the way Android M implements the lock screen. Instead of the camera and phone shortcuts, you have camera and voice search. Voice Search is accessed by swiping from the lower left corner where you now have a mic icon.

The voice command interface that pops up when you swipe the icon will look familiar—it's the same half-screen white card used everywhere. The dialer is still accessible from a securely locked device when you pull up the pattern/password screen. There's a link for emergency calls at the bottom. If you want to make a regular call you'd obviously have to unlock the device, so a dialer shortcut is a bit redundant on the lock screen in the first place.