RFR: 8292625: jshell crash on "var a = a" [v3]

[Bo Zhang]

> This commit adds the missing `type` assignment when attributing a variable's initial value. In some cases, this issue causes an NPE.
> 
> This issue has existed for a long time, but the NPE was swallowed until https://github.com/openjdk/jdk/commit/433394203dce55db95caefcb57bac9ec114ebc47 stopped swallowing such exceptions.

Bo Zhang has updated the pull request incrementally with one additional commit since the last revision:

  Resolve review feedback

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Changes:
  - all: https://git.openjdk.org/jdk/pull/11263/files
  - new: https://git.openjdk.org/jdk/pull/11263/files/5c58e847..8bb111b8

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=11263&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=11263&range=01-02

  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/11263.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11263/head:pull/11263

PR: https://git.openjdk.org/jdk/pull/11263