This change adds a dry run mode to plaster, that can be called with:
```sh
tools/cr/plaster.py check
```
This command can also be called with a list of files, that can be either
`rewrite/` files or `patches/` files.
We are also adding support to plaster for .patchinfo files, allowing a
more efficient way to make sure any given plaster file has should be
regenerated.
### What does plaster do to .patchinfo files
Plaster now generates the contents of a .patchinfo file, and based on
that content it determines if one of these files must be updated:
source, patch, or patchinfo (a combination of npm run update_patches
and npm run apply_patches). A new key is being added to the patchinfo
format, namely, plaster, which is used to store the path and checksum
for the plaster file for a given patch/source set. Files are only
updated on disk if the resulting new content doesn't match the hash of
the file saved in disk.
For now plaster always produce a .patchfile when processing a plaster,
to avoid unnecessary writes and to confirm that submitted patches do
have the expected content. This may change in the future with a more
mature approach where the contents of the patchinfo file may be used
to avoid running all the plaster transformations. This means that for
now we have to pay for a full plaster generation to determine if a file
source/patch/patchinfo are out-of-date.
Resolves https://github.com/brave/brave-browser/issues/47066
cdesouza-chromium
407770c2cb