CrOS: Update public waterfall to auto-configure.

masters/master.chromiumos/chromiumos_board_config.py

+# Copyright (c) 2015 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import collections
+import logging
+import sys
+
+from common.slave_alloc import SlaveAllocator
+from common.cros_chromite import Get, ChromiteTarget
+from master.cros import builder_config
+
+
+# Declare a slave allocator. We do this here so we can access the slaves
+# configured by 'slaves.cfg' in 'master.cfg'.
+slave_allocator = SlaveAllocator()
+
+
+# Get the pinned Chromite configuration.
+cbb_config = Get(allow_fetch=True)
+
+
+# Select any board that is configured to build on this waterfall.
+def _GetWaterfallTargets():
+  result = collections.OrderedDict()
+  for config in cbb_config.itervalues():
+    if config.get('active_waterfall') != 'chromiumos':
+      continue
+    result[config.name] = config
+  return result
+waterfall_targets = _GetWaterfallTargets()
+
+
+# Load the builder configs.
+builder_configs = builder_config.GetBuilderConfigs(waterfall_targets)
+builder_name_map = dict((c.builder_name, c)
+                        for c in builder_configs.itervalues())