Add support for generating builder_group property.

Bug: 1109276
Change-Id: Ief72c4d315bb12cb588454cc09555e6e6f6e51b0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2362995
Auto-Submit: Garrett Beaty <gbeaty@chromium.org>
Reviewed-by: Erik Staab <estaab@chromium.org>
Commit-Queue: Erik Staab <estaab@chromium.org>
Cr-Commit-Position: refs/heads/master@{#799199}

infra/config/lib/builders.star

@@ -236,6 +236,7 @@ defaults = args.defaults(
 
     # Our custom arguments
     auto_builder_dimension = args.COMPUTE,
+    builder_group = None,
     builderless = args.COMPUTE,
     bucketed_triggers = False,
     configure_kitchen = False,
@@ -246,6 +247,7 @@ defaults = args.defaults(
     goma_enable_ats = args.COMPUTE,
     goma_jobs = None,
     goma_use_luci_auth = None,
+    # TODO(https://crbug.com/1109276) Remove mastername
     mastername = None,
     os = None,
     project_trigger_overrides = None,
@@ -278,6 +280,8 @@ def builder(
         auto_builder_dimension = args.DEFAULT,
         cores = args.DEFAULT,
         cpu = args.DEFAULT,
+        builder_group = args.DEFAULT,
+        # TODO(https://crbug.com/1109276) Remove mastername
         mastername = args.DEFAULT,
         pool = args.DEFAULT,
         ssd = args.DEFAULT,
@@ -325,8 +329,12 @@ def builder(
         machines devoted to the builder. If True, a dimension will be emitted of
         the form 'builder:<name>'. By default, considered True iff `builderless`
         is considered False.
-      * mastername - a string with the mastername of the builder. Emits a property
+      * builder_group - a string with the group of the builder. Emits a property
+        of the form 'builder_group:<builder_group>'. By default, considered None.
+      * mastername - a string with the group of the builder. Emits a property
         of the form 'mastername:<mastername>'. By default, considered None.
+        Other than the property emitted, should be treated the same as
+        builder_group. At most one of builder_group or mastername can be set.
       * cores - an int indicating the number of cores the builder requires for the
         machines that run it. Emits a dimension of the form 'cores:<cores>' will
         be emitted. By default, considered None.
@@ -435,7 +443,13 @@ def builder(
     if cpu != None:
         dimensions["cpu"] = cpu
 
+    builder_group = defaults.get_value("builder_group", builder_group)
     mastername = defaults.get_value("mastername", mastername)
+    if builder_group != None and mastername != None:
+        fail("builder_group and mastername cannot both be set")
+
+    if builder_group != None:
+        properties["builder_group"] = builder_group
     if mastername != None:
         properties["mastername"] = mastername
 

infra/config/lib/ci.star

@@ -396,8 +396,7 @@ def console_view_entry(*, category = None, short_name = None):
 
     Returns:
       A struct that can be passed to the `console_view_entry` argument of
-      `ci.builder` to add an entry to the console for the builder's
-      mastername.
+      `ci.builder` to add an entry to the console for the builder's group.
     """
     return struct(
         category = category,
@@ -425,7 +424,7 @@ def ci_builder(
         False.
       console_view - A string identifying the ID of the console view to
         add an entry to. Supports a module-level default that defaults to
-        the mastername of the builder, if provided. An entry will be added
+        the group of the builder, if provided. An entry will be added
         only if `add_to_console_view` is True and `console_view_entry` is
         provided.
       main_console_view - A string identifying the ID of the main console
@@ -466,7 +465,11 @@ def ci_builder(
     if console_view_entry:
         console_view = defaults.get_value("console_view", console_view)
         if console_view == args.COMPUTE:
-            console_view = defaults.get_value_from_kwargs("mastername", kwargs)
+            # The builder function guarantees that at most one of builder_group
+            # or mastername is set
+            builder_group = defaults.get_value_from_kwargs("builder_group", kwargs)
+            mastername = defaults.get_value_from_kwargs("mastername", kwargs)
+            console_view = builder_group or mastername
 
         if console_view:
             add_to_console_view = defaults.get_value(
@@ -907,12 +910,18 @@ def swangle_windows_builder(*, name, **kwargs):
 def thin_tester(
         *,
         name,
-        mastername,
         triggered_by,
+        # TODO(https://crbug.com/1109276) Remove mastername and remove default
+        # for builder_group
+        builder_group = None,
+        mastername = None,
         tree_closing = True,
         **kwargs):
+    if builder_group == None and mastername == None:
+        fail("One of builder_group or mastername must be set")
     return ci.builder(
         name = name,
+        builder_group = builder_group,
         mastername = mastername,
         triggered_by = triggered_by,
         goma_backend = None,

infra/config/lib/try.star

@@ -212,7 +212,7 @@ def try_builder(
         be added as includable_only.
       list_view - A string identifying the ID of the list view to
         add an entry to. Supports a module-level default that defaults to
-        the mastername of the builder, if provided. An entry will be added
+        the group of the builder, if provided. An entry will be added
         only if `add_to_list_view` is True.
       main_console_view - A string identifying the ID of the main list
         view to add an entry to. Supports a module-level default that
@@ -257,7 +257,11 @@ def try_builder(
     if add_to_list_view:
         list_view = defaults.get_value("list_view", list_view)
         if list_view == args.COMPUTE:
-            list_view = defaults.get_value_from_kwargs("mastername", kwargs)
+            # The builder function guarantees that at most one of builder_group
+            # or mastername is set
+            builder_group = defaults.get_value_from_kwargs("builder_group", kwargs)
+            mastername = defaults.get_value_from_kwargs("mastername", kwargs)
+            list_view = builder_group or mastername
 
         if list_view:
             add_to_list_view = defaults.get_value(