Make getParameters() return scaleResolutionDownTo when set.
When this parameter is set you should be able to see it in
getParameters(). We somehow forgot to test this in WPTs but it is needed
for "get + set parameters" not to reset existing settings and seeing
this value is the most straightforward way to feature detect this API.
Bug: chromium:374254320
Change-Id: I4897189cca29751a3cf22d7f928bf3a81a10c984
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5938239
Reviewed-by: Harald Alvestrand hta@chromium.org
Commit-Queue: Henrik Boström hbos@chromium.org
Cr-Commit-Position: refs/heads/main@{#1371266}