tree 52a2a80d007542b7b35c7c8c451577be74596d7a
parent a131c0871c679b61f4ad7b8ea89913814ff11907
author Lukasz Anforowicz <lukasza@google.com> 1757724923 -0700
committer Pdfium LUCI CQ <pdfium-scoped@luci-project-accounts.iam.gserviceaccount.com> 1757724923 -0700

[rust png] Introduce separate `enum class DecodingColorType`.

Having a separate `DecodingColorType` means that:

* `DecodingColorType` can have just 2 variants.  And this means that
  drop `NOTREACHED` `case`s from a `switch` in `png_decoder.cpp` and
  then hoist the only remaining `case` out of the `switch` (dropping
  the `switch`ing altogether)
* The variants of `DecodingColorType` can be named more directly
  (truecolor doesn't necessarily imply BGR vs RGB).  And this in turn
  should hopefully make follow-up Skia integration easier.
* "in-out" parameter of `PngReadHeader` can be replaced with two
  separate parameters - one "in", and one "out".  This seems easier
  to read and understand than the old code.

Bug: 444045690
Change-Id: I93ac808159404d6bd45a0a4e3df8976b2e4d4b2e
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/135615
Commit-Queue: Łukasz Anforowicz <lukasza@google.com>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>