In some versions of TypeScript, the transformation of synthetic
`$localize` tagged template literals is broken.
See https://github.com/microsoft/TypeScript/issues/38485
We now compute what the expected final output target of the
compilation will be so that we can generate ES5 compliant
`$localize` calls instead of relying upon TS to do the downleveling
for us.
This is a workaround for the TS compiler bug, which could be removed
when this is fixed. But since it only affects ES5 targeted compilations,
which is now not the norm, it has limited impact on the majority of
Angular projects. So this fix can probably be left in indefinitely.
PR Close#36989
4e1b5e43fa