chromiumos: add ChromeOS classic merge controls

We create a label and require it for submission on release branch M131,
and in the future we will require it on all future chromeos release
branches (M131+).

See: go/cros-merge-controls

Bug: 382559767
Change-Id: Id246033578ba6d5bd1e79271a7a58ea26a93d8bb
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/+/6071977
Reviewed-by: Andrew Mitchell <[email protected]>
Commit-Queue: George Engelbrecht <[email protected]>
Reviewed-by: Gavin Mak <[email protected]>
diff --git a/groups b/groups
index f28f776..e235417 100644
--- a/groups
+++ b/groups
@@ -45,3 +45,4 @@
 mdb:kokoro                                                    	mdb/kokoro
 mdb:kokoro-dedicated                                          	mdb/kokoro-dedicated
 mdb:meet-devices-onduty-team                                  	mdb/meet-devices-onduty-team
+mdb:cros-release-merge-approvers                              	mdb/cros-release-merge-approvers
diff --git a/project.config b/project.config
index 0567a7f..4b6cac1 100644
--- a/project.config
+++ b/project.config
@@ -217,3 +217,21 @@
 	submittableIf = label:Code-Review=MAX,user=non_uploader -label:Code-Review=MIN
 	overrideIf = label:Bot-Commit=+1 AND -label:Code-Review=MIN
 	canOverrideInChildProjects = true
+[label "Release-Branch-Merge-Approval"]
+	value = -1 Merge Denied
+	value = 0 Not Approved
+	value = +1 Yolo
+	defaultValue = 0
+	function = NoBlock
+	copyCondition = changekind:NO_CHANGE OR changekind:NO_CODE_CHANGE OR changekind:TRIVIAL_REBASE
+	branch = refs/heads/release-R131-16063.B
+	description = This release branch is protected by merge controls (go/cros-merge-controls)
+[submit-requirement "MergeApprovedYolo"]
+	description = Submit requirement for Release-Branch-Merge-Approval (go/cros-merge-controls)
+	applicableIf = branch:refs/heads/release-R131-16063.B
+	submittableIf = label:Release-Branch-Merge-Approval=MAX
+	canOverrideInChildProjects = true
+	overrideIf = uploader:[email protected] OR uploader:[email protected] OR uploader:[email protected]
+[access "refs/heads/release-R131-16063.B"]
+	exclusiveGroupPermissions = label-Release-Branch-Merge-Approval
+	label-Release-Branch-Merge-Approval = -1..+1 group mdb/cros-release-merge-approvers