Setup default RBE usage including facilitating CI RBE usage. (#727)

.github/actions/build/action.yaml

@@ -16,6 +16,9 @@ runs:
       - name: Add depot tools to PATH
         run: echo "$GITHUB_WORKSPACE/depot_tools" >> $GITHUB_PATH
         shell: bash
+      - name: Disable Chromium client side build telemetry
+        run: build_telemetry opt-out
+        shell: bash
       - name: Generate gclient file
         run: gclient config --name=src https://github.com/${{ github.repository }} --custom-var=download_remoteexec_cfg=True
         shell: bash

DEPS

@@ -264,7 +264,7 @@ vars = {
   'rbe_instance': Str('projects/cobalt-actions-devel/instances/default_instance'),
   # RBE project to download rewrapper config files for. Only needed if
   # different from the project used in 'rbe_instance'
-  'rewrapper_cfg_project': Str('rbe-chrome-untrusted'),
+  'rewrapper_cfg_project': Str(''),
   # reclient CIPD package
   'reclient_package': 'infra/rbe/client/',
   # reclient CIPD package version