Keep a tabular array initializer with mixed signs in rows

[abashev]

Brings over google/google-java-format#406 by Andrew Reid, which fixes google/google-java-format#400 (google-java-format 1.8).

The bug

An array initializer written in rows, such as a table of coordinates, keeps its rows when every column holds expressions of the same kind. A column that mixed 95.0 with -95.0 or +95.0 did not count as one kind, because a signed number is a unary expression in javac's tree, so the whole table collapsed into one line:

    private static final double[] g = {95.0, 75.0, -95.0, 75.0, -95.0, 75.0, +95.0, 75.0};

while the same table without signs kept its two rows.

From upstream, with the author kept

• Preserve tabular arguments for mixed sign numeric lists. google/google-java-format#406 by Andrew Reid, commit authored by them: in expressionsAreParallel a unary expression counts as the kind of its operand. The upstream golden TabularMixedSignInitializer comes with it (signs, ++/--/~ and ! columns), with the expected output in this project's style.

Checked

• The golden fails on main and passes with the change.
• ./gradlew :open-java-format:test on JDK 21: 1501 tests, all green.
• The 15,747 files of the JDK 21 sources format exactly as before.