Previously, an instance of HttpParams would retain its list of mutations
after they have been materialized as a result of a read operation. Not
only does this unnecessarily hold onto memory, more importantly does it
introduce a bug where branching of off a materialized instance would
reconsider the set of mutations that had already been applied, resulting
in repeated application of mutations.
This commit fixes the bug by clearing the list of pending mutations
after they have been materialized, such that they will not be considered
once again for branched off instances.
Fixes#20430
PR Close#29045
This is necessary to enable type-based optimizations with Closure.
Without explicity making these options the same named type, Closure
thinks they are different types and cannot disambiguate the `fromObject`
property.
Today, constructing a new GET request with headers looks like:
const headers = new HttpHeaders({
'My-Header': 'header value',
});
http.get('/url', {headers}).subscribe(...);
This indirection is unnecessary. It'd be more ergonomic to write:
http.get('/url', {headers: {'My-Header': 'header value'}}).subscribe(...);
This commit allows that new syntax, both for HttpHeaders and HttpParams.
In the HttpParams case it also allows construction of HttpParams with a map.
PR Close#18490
