Allow a single trybot to mirror multiple waterfall bots.

scripts/slave/recipe_modules/perf_try/api.py

Index: scripts/slave/recipe_modules/perf_try/api.py
diff --git a/scripts/slave/recipe_modules/perf_try/api.py b/scripts/slave/recipe_modules/perf_try/api.py
index db284dafc3ba420b53b1920de007486ab10662c4..29f48c8ec8b670d4b98a6182cbf6680d296c49b8 100644
--- a/scripts/slave/recipe_modules/perf_try/api.py
+++ b/scripts/slave/recipe_modules/perf_try/api.py
@@ -162,8 +162,7 @@ class PerfTryJobApi(recipe_api.RecipeApi):
   def _compile(self, name, mastername, buildername, update_step, bot_db):
     """Runs compile and related steps for given builder."""
     compile_targets, _ = self.m.chromium_tests.get_compile_targets_and_tests(
-        mastername,
-        buildername,
+        self.m.chromium_tests.create_bot_desc(mastername, buildername),
         bot_db,
         override_bot_type='builder_tester',
         override_tests=[])