RFR: 8288623: Move Continuation classes out of javaClasses.hpp [v4]

[Ioi Lam]

> javaClasses.hpp is getting too big - it contains the C++ representation of over 50 Java classes.
> 
> The RFE moves the following classes into a new file, continuationJavaClasses.hpp. The naming follows the same pattern as the existing header share/jvmci/jvmciJavaClasses.hpp.
> 
> - jdk_internal_vm_ContinuationScope
> - jdk_internal_vm_Continuation
> - jdk_internal_vm_StackChunk

Ioi Lam has updated the pull request incrementally with one additional commit since the last revision:

  @stefank review comments

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/9191/files
  - new: https://git.openjdk.org/jdk/pull/9191/files/ebc3f9f8..145e44ac

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=9191&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=9191&range=02-03

  Stats: 14 lines in 4 files changed: 5 ins; 5 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/9191.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9191/head:pull/9191

PR: https://git.openjdk.org/jdk/pull/9191