Use 'unused' instead of 'ignore' to silence Google's unused-variable …

…checker.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=187094446

src/com/google/javascript/rhino/jstype/JSTypeRegistry.java

@@ -1754,7 +1754,7 @@ public TemplateTypeMap createTemplateTypeMap(
   public ObjectTypeI instantiateGenericsWithUnknown(ObjectType obj) {
     if (obj.isTemplatizedType()) {
       ImmutableList.Builder<JSType> unknowns = ImmutableList.builder();
-      for (TemplateType ignore : obj.getTemplateTypeMap().getTemplateKeys()) {
+      for (TemplateType unused : obj.getTemplateTypeMap().getTemplateKeys()) {
         unknowns.add(getNativeType(UNKNOWN_TYPE));
       }
       return createTemplatizedType(obj.toMaybeTemplatizedType().getRawType(), unknowns.build());