Varifier false positive when the declared type is annotated

[ben-manes]

When enabling NullAway's jspecify mode, the use of arrays needs to be annotated for stricter nullability. For example,

.../LocalAsyncCache.java:818: warning: [NullAway] Writing @Nullable expression into array with @NonNull contents.
          oldValue[0] = Async.getIfReady(oldValueFuture);

To satisfy this check without a suppression requires the change

-var oldValue = (V[]) new Object[1];
+@Nullable V[] oldValue = (V[]) new Object[1];

ErrorProne then emits a warning,

.../LocalAsyncCache.java:800: warning: [Varifier] Consider using `var` here to avoid boilerplate.
      @Nullable V[] oldValue = (V[]) new Object[1];
                    ^
    (see https://errorprone.info/bugpattern/Varifier)
  Did you mean '@Nullable var oldValue = (V[]) new Object[1];'?

However that suggestion is invalid by JLS and instead the warning must be suppressed.

.../LocalAsyncCache.java:800: error: annotation interface not applicable to this kind of declaration
        @Nullable var oldValue = (V[]) new Object[1];
        ^
  1 error

Note that the annotation is not carried forward in the inferred type for NullAway to use if instead trying to resolve both checks

var oldValue = (@Nullable V[]) new Object[1];