RFR: 8256325: Remove duplicate asserts in PhaseMacroExpand::expand_macro_nodes [v2]

[Tobias Hartmann]

> [JDK-8239072](https://bugs.openjdk.java.net/browse/JDK-8239072) added a default case to the switch statement in PhaseMacroExpand::expand_macro_nodes:
> https://hg.openjdk.java.net/jdk/jdk/rev/cf319f17c647#l3.67
> 
> This allows to merge the "expansion must have deleted one node from macro list" asserts and remove the duplicate asserts.
> 
> Thanks,
> Tobias

Tobias Hartmann has updated the pull request incrementally with one additional commit since the last revision:

  Uppercase DEBUG_ONLY

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/1200/files
  - new: https://git.openjdk.java.net/jdk/pull/1200/files/c3dde8c5..db3af879

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=1200&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=1200&range=00-01

  Stats: 4 lines in 1 file changed: 0 ins; 0 del; 4 mod
  Patch: https://git.openjdk.java.net/jdk/pull/1200.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/1200/head:pull/1200

PR: https://git.openjdk.java.net/jdk/pull/1200