PY-87617 Fix WSL browse dialog when text field is null

There was a problem when browse dialog was invoked with null value in
the text field. This is possible when the field is a combo box, but
there are no values present.

The fix is to fallback to default directory (user home and then root) in
case of null in the text field.

GitOrigin-RevId: ebd4f834ab696017ddb6fcaf02e0b519e3decc33

platform/execution-impl/src/com/intellij/execution/wsl/target/WslTargetType.kt

@@ -79,7 +79,7 @@ class WslTargetType : TargetEnvironmentType<WslTargetEnvironmentConfiguration>(T
     configuration.distribution?.let {
       val textAccessor = object : TextAccessor {
         override fun setText(text: String) = textComponentAccessor.setText(component, text)
-        override fun getText() = textComponentAccessor.getText(component)
+        override fun getText(): @NlsSafe String = textComponentAccessor.getText(component) ?: it.userHome ?: "/"
       }
       browseWslPath(textAccessor,
                     it,