component/headless-chromium: clone full source

Cloning the full source tree rather than just a snapshot at the desired
version does increase the size of the checkout, but not as much as
originally feared. It goes from 25 GB -> 31 GB, which is manageable.
On the other hand, this allows some automated tools to figure out the
commit hashes from the repository history, which prevents the frontend
from complaining.

I plan to clean up the buildout file in the future, but I just wanted
to commit a known-working version.

component/headless-chromium/buildout.cfg

@@ -30,6 +30,7 @@ parts =
 # There's nothing special about version 91.0.4472.132. It just happened to be
 # the current Chromium stable version at the time of writing.
 # TODO: set source URL as a parameter to avoid duplication?
+# TODO: change to use either slapos.recipe.build:gitclone or depot tools fetch. Note that if you use gitclone, set develop = true.
 [chromium-source]
 recipe = plone.recipe.command
 path = ${buildout:parts-directory}/${:_buildout_section_name_}
@@ -39,10 +40,9 @@ command =
   rm -rf ${:path}
   mkdir -p ${:path}
   cd ${:path}
-  git clone \
-    --branch ${:version} \
-    --depth 1 \
-    https://chromium.googlesource.com/chromium/src.git
+  git clone https://chromium.googlesource.com/chromium/src.git
+  cd src
+  git checkout ${:version}
 
 [chromium]
 recipe = slapos.recipe.cmmi