Don't fail on warnings in the gold SDK

We shouldn't have errors, but we should lean towards the dev release

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=152153305

Author: kevmoo

.travis.yml

@@ -29,7 +29,7 @@ matrix:
         dartanalyzer: --fatal-warnings lib
     - dart: stable
       dart_task:
-        dartanalyzer: --fatal-warnings lib
+        dartanalyzer:
 cache:
   directories:
     - $HOME/.pub-cache