Respect multiple styles in chooseFile and chooseFiles methods

[imagejan]

We currently check for equality in the chooseFile and chooseFiles methods of AbstractSwingUI:

scijava-ui-swing/src/main/java/org/scijava/ui/swing/AbstractSwingUI.java

Line 145 in 2439a55

if (FileWidget.DIRECTORY_STYLE.equals(style)) {

scijava-ui-swing/src/main/java/org/scijava/ui/swing/AbstractSwingUI.java

Line 176 in 2439a55

if (style.equals(FileListWidget.FILES_AND_DIRECTORIES)) {

Let's instead use a common utility method to check whether a certain style string matches a given widget style.

See also scijava/scijava-common#333.