@Override
	public void setComponentDataTypeInstance(int rowIndex, DataType dt, int length)
			throws UsrException {
		if (getComponent(rowIndex) == null) {
			// Replacing data type in unlocked mode replaces only
			// that data type and structure size may change.
			insert(rowIndex, dt, length);
		}
		else {
			// Replacing data type in unlocked mode replaces only
			// that data type and structure size may change.
			replace(rowIndex, dt, length);
		}
	}
Cause the component at the specified index to consume undefined bytes
that follow it.
Note: this method adjusts the selection.

@param rowIndex the row index
@return the number of Undefined bytes consumed.
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/compositeeditor/CompEditorModel.java