A child element cannot be marked legacy=true if its parent is removed without legacy support:
{% include “docs/reference/fidl/language/error-catalog/label/_bad.md” %}
{% includecode gerrit_repo="fuchsia/fuchsia" gerrit_path="tools/fidl/fidlc/tests/fidl/bad/fi-0183.test.fidl" exclude_regexp="\/\/ (Copyright 20|Use of|found in).*" %}
Instead, remove the legacy=true argument:
{% include “docs/reference/fidl/language/error-catalog/label/_good.md” %}
{% includecode gerrit_repo="fuchsia/fuchsia" gerrit_path="tools/fidl/fidlc/tests/fidl/good/fi-0183-a.test.fidl" exclude_regexp="\/\/ (Copyright 20|Use of|found in).*" %}
Alternatively, add legacy=true to the parent as well. The child will inherit it, so it's not necessary to specify it again there. Note that this will also affect any other children the parent has.
{% include “docs/reference/fidl/language/error-catalog/label/_good.md” %}
{% includecode gerrit_repo="fuchsia/fuchsia" gerrit_path="tools/fidl/fidlc/tests/fidl/good/fi-0183-b.test.fidl" exclude_regexp="\/\/ (Copyright 20|Use of|found in).*" %}
The legacy=true argument indicates an element should be added back at the LEGACY version after being removed, and a child element cannot exist independently of its parent. See the documentation on legacy for more details.
