[foreign-jextract] RFR: 8261337: jextract error message when directory is passed as header file argument

[Maurizio Cimadamore]

On Mon, 8 Feb 2021 14:16:43 GMT, Athijegannathan Sundararajan <sundar at openjdk.org> wrote:

> directory-as-header is detected upfront before parsing and proper error message is issued.

Looks good

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Marked as reviewed by mcimadamore (Committer).

PR: https://git.openjdk.java.net/panama-foreign/pull/448