For now, I fixed this with changing in the wear build.gradle:
compile 'com.google.android.support:wearable:2.0.3'
provided 'com.google.android.wearable:wearable:2.0.3'
It seems like the problem is com.google.android.support:wearable:2.0.4. With that, Using 26.0.1 build tools compiles fine. I haven't gone any further with this but it looks like a dependency problem related to a repository although that is really just a guess from the error messages.