Use getAPattern

Author: smowton

java/ql/lib/semmle/code/java/Statement.qll

@@ -559,9 +559,7 @@ class PatternCase extends SwitchCase {
   /**
    * Gets this case's sole pattern, if there is exactly one.
    */
-  PatternExpr getUniquePattern() {
-    result = unique(PatternExpr pe | pe = this.getPatternAtIndex(_))
-  }
+  PatternExpr getUniquePattern() { result = unique(PatternExpr pe | pe = this.getAPattern()) }
 
   /** Gets the guard applicable to this pattern case, if any. */
   Expr getGuard() { result.isNthChildOf(this, -3) }