[cr-buildbucket] Add remaining master mixins

This adds master mixins for:
* chromium
* chromium.chromedriver
* chromium.lkgr
* chromium.swarm

Bug: 840631
Change-Id: Ia615d68243c114bc61b44ec2179e1b5830ea02d5
Reviewed-on: https://chromium-review.googlesource.com/1063167Reviewed-by: Andrii Shyshkalov <tandrii@chromium.org>
Commit-Queue: Ryan Tseng <hinoka@chromium.org>
Cr-Commit-Position: refs/heads/master@{#559373}

infra/config/global/cr-buildbucket.cfg

@@ -163,6 +163,13 @@ builder_mixins {
   }
 }
 
+builder_mixins {
+  name: "chromedriver-ci"
+  recipe {
+    properties: "mastername:chromium.chromedriver"
+  }
+}
+
 builder_mixins {
   name: "chromeos-ci"
   # All CrOS building is done via cross-compilation on linux hosts, so use the
@@ -184,6 +191,13 @@ builder_mixins {
   }
 }
 
+builder_mixins {
+  name: "chromium-ci"
+  recipe {
+    properties: "mastername:chromium"
+  }
+}
+
 builder_mixins {
   name: "fyi-ci"
   recipe {
@@ -234,6 +248,13 @@ builder_mixins {
   }
 }
 
+builder_mixins {
+  name: "lkgr-ci"
+  recipe {
+    properties: "mastername:chromium.lkgr"
+  }
+}
+
 builder_mixins {
   name: "memory-ci"
   mixins: "goma-many-jobs-for-ci"
@@ -350,6 +371,13 @@ builder_mixins {
   dimensions: "cores:4"
 }
 
+builder_mixins {
+  name: "swarm-ci"
+  recipe {
+    properties: "mastername:chromium.swarm"
+  }
+}
+
 builder_mixins {
   name: "webkit-ci"
   recipe {