TableSkinUtils should not contain actual code implementation

Summary

Add a new protected method in TableColumnHeader allowing developers to override the algorithm used for resizing a column to fit its content.

Problem

The method resizeColumnToFitContent(TableViewSkinBase<?,?,?,?,?> tableSkin, TableColumnBase<?,?> tc, int maxRows) in javafx.scene.control.skin.TableSkinUtils cannot be accessed by a person overriding the TableView. Therefore, it is not possible for a developer to provide a custom implementation for a column being resized.

Solution

A solution is to remove the implementation from TableSkinUtils and move it somewhere, where it could be overridden. A 1st solution is to revert back to java 8 API and place this method in TableViewSkinBase but that would introduce an abstract method.

A 2nd solution is to naturally place this method in the TableColumnHeader class since it's this specific class that will call this method.

Specification

The following API is added:

javafx/scene/control/skin/TableColumnHeader.java :

/**
 * Resizes this {@code TableColumnHeader}'s column to fit the width of its content.
 *
 * @implSpec The resulting column width for this implementation is the maximum of the preferred width of the header
 * cell and the preferred width of the first {@code maxRow} cells.
 * <p>
 * Subclasses can either use this method or override it (without the need to call {@code super()}) to provide their
 * custom implementation (such as ones that exclude the header, exclude {@code null} content, compute the minimum
 * width, etc.).
 *
 * @param maxRows the number of rows considered when resizing. If -1 is given, all rows are considered.
 * @since 14
 */
protected void resizeColumnToFitContent(int maxRows) {