Allow @OverRide* annotations to use /**, like in JsDoc.

Including the one I forgot in CL 129239548

This is a rollforward.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=129287698

src/com/google/common/css/compiler/passes/CheckMissingRequire.java

@@ -54,10 +54,10 @@ public final class CheckMissingRequire extends DefaultTreeVisitor implements Css
   private static final Logger logger = Logger.getLogger(CheckMissingRequire.class.getName());
 
   private static final Pattern OVERRIDE_SELECTOR_REGEX = Pattern.compile(
-      "/\\*\\s+@overrideSelector\\s+\\{(.*)\\}\\s+\\*/");
+      "/\\*\\*?\\s+@overrideSelector\\s+\\{(.*)\\}\\s+\\*/");
 
   private static final Pattern OVERRIDE_DEF_REGEX = Pattern.compile(
-      "/\\*\\s+@overrideDef\\s+\\{(.*)\\}\\s+\\*/");
+      "/\\*\\*?\\s+@overrideDef\\s+\\{(.*)\\}\\s+\\*/");
 
   private final VisitController visitController;
   private final ErrorManager errorManager;