Manual metrics created from Java plugins should not be updated online

Sonar administrator can insert measures online on some specific metrics (characteristic "user_managed" of a metric). Those metrics can be created online (page Configuration --> Manual metrics) or by a Java plugin (example : sonar-plugin-core defines the metrics Team size, Business Value and Burned Budget).
Metrics defined by a Java plugin are created/updated each time the server starts, overriding changes made online.

That's why an administrator should not updade or delete online a metric generated by a Java plugin. Edit and delete buttons must be removed.