Wolverine Appearances:
X-Men 1-3
Origins
The Wolverine
First Class (Cameo)
Days of Future Past

Well, yeah, Stryker's always been a big part of the whole Weapon X/ Wolverine/ Lady Deathstrike/ Deadpool/ Sabertooth thing. My point was the movies aren't exactly faithful to the source material in quite a few ways to begin with, so I wouldn't worry much about what's different.