Remove unused new method

Author: garydgregory

src/main/java/org/apache/commons/io/build/AbstractOriginSupplier.java

@@ -45,19 +45,6 @@
  */
 public abstract class AbstractOriginSupplier<T, B extends AbstractOriginSupplier<T, B>> extends AbstractSupplier<T, B> {
 
-    /**
-     * Throws {@link IllegalArgumentException} if the initialBufferSize is less than zero.
-     *
-     * @param initialBufferSize the value to test.
-     * @return the input value.
-     */
-    protected static int checkBufferSize(final int initialBufferSize) {
-        if (initialBufferSize < 0) {
-            throw new IllegalArgumentException("Initial buffer size must be at least 0.");
-        }
-        return initialBufferSize;
-    }
-
     /**
      * Creates a new byte array origin for a byte array.
      *