hg: jdk/sandbox: flatmap-branch: refactor FlatPushConsumer and add test cases

[julia.boes at oracle.com]

Changeset: cefe4d2986ec
Author:    jboes
Date:      2020-03-30 14:50 +0100
URL:       https://hg.openjdk.java.net/jdk/sandbox/rev/cefe4d2986ec

flatmap-branch: refactor FlatPushConsumer and add test cases

! src/java.base/share/classes/java/util/stream/FlatPushConsumer.java
! src/java.base/share/classes/java/util/stream/ReferencePipeline.java
! src/java.base/share/classes/java/util/stream/Stream.java
! test/jdk/java/util/stream/test/org/openjdk/tests/java/util/stream/FlatPushOpTest.java