Bug
1563460 - Collect console messages generated by processing manifest for Dev Tools r=baku
This gets rid of the sending warnings to the browser console. Instead, when the processor is explicitly asked to do so, it now collects spec violations into a `moz_validation` member.
To access the new manifest member, you can now pass a second argument to `ManifestObtainer.contentObtainManifest()` like so:
```
const manifest = await ManifestObtainer.contentObtainManifest(
this.targetActor.window,
{ checkConformance: true }
);
manifest. moz_validation; // 🎉
```
Differential Revision: https://phabricator.services.mozilla.com/D36885
--HG--
extra : moz-landing-system : lando