Support "mandatoryProvidersList" in Skylark and added necessary tests

The type of attribute "providers" now is a list of lists of string. But a list
of string is still supported.

--
MOS_MIGRATED_REVID=115357326

1 files changed, 2 insertions, 1 deletions

diff --git a/src/test/java/com/google/devtools/build/lib/generatedprojecttest/util/RuleSetUtils.java b/src/test/java/com/google/devtools/build/lib/generatedprojecttest/util/RuleSetUtils.java
index 2bb34a9f21..32b9c83782 100644
--- a/src/test/java/com/google/devtools/build/lib/generatedprojecttest/util/RuleSetUtils.java
+++ b/src/test/java/com/google/devtools/build/lib/generatedprojecttest/util/RuleSetUtils.java
@@ -48,7 +48,8 @@ public class RuleSetUtils {
         RuleClassType.INVISIBLE.checkName(input);
         return true;
       } catch (IllegalArgumentException e) {
-        return input.equals("testing_dummy_rule");
+        return input.equals("testing_dummy_rule")
+            || input.equals("testing_rule_for_mandatory_providers");
       }
     }
   };