Strange Unknown Leaf Spots

Description:

These odd spots were all over on leaves of this plant. If it had been a single spot, I would have thought it was some kind of bird dropping. There were so many and mostly of the same size that it must be some kind of insect caused plant response. The plant cells under the spots are obviously affected. The spots consist of slightly raised black tar-like stuff (but not sticky). Has anyone ever seen something like this?

Habitat:

Totem Bight State Park, Ketchikan, Alaska.