It's possible to declare multiple inputs for a directive/component which all
map to the same property name. This is usually done in error, as only one of
any bindings to the property will "win".
In the template type-checker, an error was previously being raised as a
result of this ambiguity. Specifically, a type constructor was produced
which required a binding for each field, but only one of the fields had
a value via the binding. TypeScript would (rightfully) error on missing
values for the remaining fields. This ultimately was happening when the
code which generated the default values for "unset" inputs belonging to
directives or pipes used the final mapping from properties to fields as
a source for field names.
Instead, this commit uses the original list of fields to generate unset
input values, which correctly provides values for fields which shared a
property name but didn't receive the final binding.
PR Close#34649
22c957a93d