isFullyVisible = function(sColumn) {
				return oNewWidths[sColumn] >= FlexibleColumnLayout.COLUMN_MIN_WIDTH;
			}
Merges the default (or previously saved) column widths [for the given layout]
with the updated column widths upon interactive resize [when the user dragged
the column separators]
@param {object} oOptions the oprions
@param {Object<string,number>} oOptions.oldWidths the default (or previously saved) column widths
for the given layout
@param {Object<string,number>} oOptions.newWidths the new  column widths produced
upon interactive resize, when the user dragged the column separators
@param {sap.f.LayoutType} oOptions.sLayout the layout
@param {"begin"|"mid"|"end"} oOptions.columnEnlargedByDragging the name of the column
enlarged during interactive resize
@returns {Object<string,number>} the merged widths