Cleanup network_utils::ParseDataURLAndPopulateResponse

It no longer mutates the parameter response. Rename it to ParseDataURL.
|verify_mime_type| parameter is confusing, so move the logic out of the
function.

Bug: 704032
Change-Id: Icecfaa6e96ddc783f4007ec290ec42f6f48c0065
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1520511
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Reviewed-by: Makoto Shimazu <shimazu@chromium.org>
Commit-Queue: Yutaka Hirano <yhirano@chromium.org>
Cr-Commit-Position: refs/heads/master@{#640587}
5 files changed