U - Batch 1 of CSP errors

[jmswisher]

This issue represents a time-box of work on CSP error messages. (3 points for Janet, 1 point for Sheppy)

Acceptance criteria

• A consistent structure for CSP error message articles is defined.

• The following messages can be worked on. If more can be finished within the timebox, refer to the Epic (E - CSP error messages are exposed via dev tools #316)

• The page’s settings blocked the loading of a resource: %1$S

• The page’s settings blocked the loading of a resource at %2$S (“%1$S”).

• A violation occurred for a report-only CSP policy (“%1$S”). The behavior was allowed, and a CSP report was sent.

• The page’s settings observed the loading of a resource at %2$S (“%1$S”). A CSP report is being sent.

• Tried to send report to invalid URI: “%1$S”

• couldn’t parse report URI: %1$S

• Couldn’t process unknown directive ‘%1$S’

• Ignoring unknown option %1$S

[Elchi3]

De-prioritized for now.