Fix regression in webfiles_external
Fix regression in webfiles_external

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=155460710

gramic/rules_closure,bazelbuild/rules_closure,bazelbuild/rules_closure,jart/rules_closure,gramic/rules_closure,jart/rules_closure,gramic/rules_closure,jart/rules_closure,gramic/rules_closure,jart/rules_closure,jart/rules_closure,bazelbuild/rules_closure,bazelbuild/rules_closure