GJF intellij plugin does not format files with Java 14 switch expressions

[abrudin]

When using a Java 14 switch expression in a Java source file (for example a badly formatted one like):

final TestEnum te = TestEnum.TEST1;
    final String s = switch (te) {
          case TEST1 -> "hej";
              case TEST2 -> "nej";
      };

the file does not get formatted at all when using the google-java-format plugin, whereas files without this kind of expressions work flawlessly.

This issue is present in Intellij 2020.1 with the latest google-java-format 1.7.0.5.

There was no exceptions and I found no logs, Ctrl-Alt-L just said that there was no lines changed, code already properly formatted. I tried launching Intellij with Java 14 as well, but to no avail.

[sormuras]

Related to #436 ... which is already solved on master via 4ddb914 ... but not yet packaged in the IJ IDEA plugin.

[cushon]

#436