How would a bear know the difference between a dog and a wolf? Although neither is a predator of the other, they are antagonists and tend to both be drawn to easy food. If a bear sees a dog they could think the dog was protecting a "kill cache," which could draw them right in. It all depends on where you are and what the bears are habituated to (common theme with bear safety). On the local trails around Anchorage bears are familiar with dogs, and I haven't heard of any stories where the bear was drawn to the hiker because of the dog (but that doesn't mean it doesn't happen). However, I would think in the deeper wilderness areas where bears are habituated to wolves, the bears might have a completely different reaction.
I've said it before and I will say it again: Bottom line when it comes to bears - know the bears in the area you are visiting! Don't make assumptions about bear behavior in your location based on behavior of bears elsewhere. A Kodiak Brown isn't going to act the same as a Kenai Brown, and although they are the same species, neither will act the same as a Yellowstone Grizzly.
YMMV. Viewer discretion is advised.