Previously, localized strings had very limited or incorrect source-mapping
information available.
Now the i18n AST nodes and related output AST nodes include source-span
information about message-parts and placeholders - including closing tag
placeholders.
This information is then used when generating the final localized string
ASTs to ensure that the correct source-mapping is rendered.
See #38588 (comment)
PR Close#38645
The `TagPlaceholder` can contain children, in which case there are two source
spans of interest: the opening tag and the closing tag. This commit now allows
the closing tag source-span to be tracked, so that it can be used later in
source-mapping.
PR Close#38645