RFR: 8303784: no- at Target annotations should be applicable to type parameter declarations [v5]

[Liam Miller-Cushon]

> Please consider this fix for https://bugs.openjdk.org/browse/JDK-8303784, which make `@Target`-less annotations applicable to type parameter declarations.
> 
> `@Target`-less annotations are applicable to 'all declaration contexts', which includes type parameter declarations.

Liam Miller-Cushon has updated the pull request incrementally with one additional commit since the last revision:

  Use Feature enum for version checks

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/12914/files
  - new: https://git.openjdk.org/jdk/pull/12914/files/57c4515c..749af3cc

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=12914&range=04
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=12914&range=03-04

  Stats: 4 lines in 3 files changed: 1 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/12914.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/12914/head:pull/12914

PR: https://git.openjdk.org/jdk/pull/12914