A Red Eyed-Vireo?

I went for a short walk this morning just across the street, but I changed direction as I saw a swallow change direction also as it saw me. I decided to follow the swallow around the corner of a building and down an alley as it had done so, I wondered if it might have been a cliff swallow as this species build their mud nests at this location each year. No, it wasn't a cliff swallow but I realized as It kept swooping by that it was a Tree Swallow checking out the Tree Swallow house in my neighbor's backyard. However, it wasn't a disappointing diversion as my attention was attracted to a clump of bushes nearby and I heard and saw a small bird perched mid-high on one of the branches. I immediately hoped it was a warbler, but once home and having downloaded the pictures I have decided it was a red-eyed vireo.Its breast is white and its back could be described as green (ish), but I could not distinguish a red eye, which apparently is not an unusual experience with this species in the field.
The identifying feature of this bird which I am basing my id on is the distinct dark border line on its flat gray crown. I cropped the photo and enlarged the head so this feature is shown in the photo above. So I think, a vireo it is.??