[Debug] add a screaming mode to ErrorHandler
feature #10466 [Debug] add a screaming mode to ErrorHandler (nicolas-grekas)

This PR was merged into the 2.5-dev branch.

Discussion
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[Debug] add a screaming mode to ErrorHandler

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | none
| License       | MIT
| Doc PR        | none

Collect and display silenced PHP errors in the debug toolbar.

Commits
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5cc817d [Debug] add a screaming mode to ErrorHandler