RFR: 8253751: Dependencies of automatic modules are not propagated through module layers

[Alan Bateman]

This is a corner case that arises when creating a Configuration for a child module layer. If an explicit module in the child configuration reads an automatic module in a parent configuration then it should read all automatic modules in the parent configurations. Unfortunately, this read edge wasn't created for the case that the child layer does not contain any automatic modules.

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Commit messages:
 - Merge
 - Merge
 - Add @bug to test
 - Fixed typo in comment
 - Merge
 - Merge
 - If module reads automatic module in parent configuration then reads all automatic modules

Changes: https://git.openjdk.java.net/jdk/pull/1391/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=1391&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8253751
  Stats: 86 lines in 2 files changed: 76 ins; 5 del; 5 mod
  Patch: https://git.openjdk.java.net/jdk/pull/1391.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/1391/head:pull/1391

PR: https://git.openjdk.java.net/jdk/pull/1391