[roll] Configure user.name and user.email

Follow-up to https://dart-review.googlesource.com/c/recipes/+/157960.

user.name and user.email need to be set to allow the service account to
push a merge commit.

TBR=whesse@google.com

https://github.com/dart-lang/sdk/issues/42917

Change-Id: I0c8cfbfc0e567e66c2d1f99f446a434aa9719d6a
Reviewed-on: https://dart-review.googlesource.com/c/recipes/+/158040
Reviewed-by: Alexander Thomas <athom@google.com>
Commit-Queue: Alexander Thomas <athom@google.com>
diff --git a/recipes/roller/roll_to_dev.expected/no-push-if-already-merged.json b/recipes/roller/roll_to_dev.expected/no-push-if-already-merged.json
index 790c2ef..acecc84 100644
--- a/recipes/roller/roll_to_dev.expected/no-push-if-already-merged.json
+++ b/recipes/roller/roll_to_dev.expected/no-push-if-already-merged.json
@@ -118,6 +118,28 @@
   {
     "cmd": [
       "git",
+      "config",
+      "user.name",
+      "Dart CI"
+    ],
+    "cwd": "[START_DIR]/sdk",
+    "infra_step": true,
+    "name": "configure user.name"
+  },
+  {
+    "cmd": [
+      "git",
+      "config",
+      "user.email",
+      "dart-luci-ci-builder@dart-ci.iam.gserviceaccount.com"
+    ],
+    "cwd": "[START_DIR]/sdk",
+    "infra_step": true,
+    "name": "configure user.email"
+  },
+  {
+    "cmd": [
+      "git",
       "checkout",
       "dev"
     ],
diff --git a/recipes/roller/roll_to_dev.expected/push.json b/recipes/roller/roll_to_dev.expected/push.json
index 3979cfa..4921d24 100644
--- a/recipes/roller/roll_to_dev.expected/push.json
+++ b/recipes/roller/roll_to_dev.expected/push.json
@@ -118,6 +118,28 @@
   {
     "cmd": [
       "git",
+      "config",
+      "user.name",
+      "Dart CI"
+    ],
+    "cwd": "[START_DIR]/sdk",
+    "infra_step": true,
+    "name": "configure user.name"
+  },
+  {
+    "cmd": [
+      "git",
+      "config",
+      "user.email",
+      "dart-luci-ci-builder@dart-ci.iam.gserviceaccount.com"
+    ],
+    "cwd": "[START_DIR]/sdk",
+    "infra_step": true,
+    "name": "configure user.email"
+  },
+  {
+    "cmd": [
+      "git",
       "checkout",
       "dev"
     ],
diff --git a/recipes/roller/roll_to_dev.py b/recipes/roller/roll_to_dev.py
index b9e37af..b9dce15 100644
--- a/recipes/roller/roll_to_dev.py
+++ b/recipes/roller/roll_to_dev.py
@@ -53,6 +53,13 @@
       submodule_update_recursive=False,
   )
   with api.context(cwd=api.path['checkout']):
+    api.git('config', 'user.name', 'Dart CI', name='configure user.name')
+    api.git(
+        'config',
+        'user.email',
+        'dart-luci-ci-builder@dart-ci.iam.gserviceaccount.com',
+        name='configure user.email')
+
     api.git('checkout', DEV_BRANCH, name='checkout dev')
     api.git('fetch', 'origin', commit_hash, name='fetch %s' % commit_hash)
     result = api.git(