JaCoCo is a great tool to generate tests coverage reports. Anyway, Android plugin only generates the coverage report from instrumented tests. If you want to include the unit testing, it is necessary to create the task manually.
In the task, it is possible to exclude view classes from the report, for example:
def fileFilter = [
'com/sample/**/view/**.*',
'**/R.class',
...]
Usually, I exclude Android classes (BuildConfig, R, etc) and any other XML file that is out of my test strategy.
You can find more information here:
https://docs.gradle.org/current/userguide/jacoco_plugin.html
Hope to be helpful, good luck.