RFR: 8296010: AssertionError in annotationTargetType [v4]

[Vicente Romero]

> javac is crashing if a class file is forged so that an annotation can be applicable to an unknown target. It would be equivalent to the following declaration:
> 
> 
> @Target({ElementType.FIELD, ElementType.NO_SUCH})
> @interface A {}
> 
> if the compiler process this source it would issue a compiler error, indicating that symbol `NO_SUCH` cant be found. Currently our class reader just issues a warning and move on. This is OK as it could be that the loaded class won't be used anyway but if this annotation is actually applied to symbol as in:
> 
> 
> class B {
>     @A Object o;
> }
> 
> then this to my understanding should be a compilation error. Currently javac is crashing and this is not acceptable, so this PR is fixing this issue so that a compilation error is issued instead.

Vicente Romero has updated the pull request incrementally with one additional commit since the last revision:

  minor update

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/12241/files
  - new: https://git.openjdk.org/jdk/pull/12241/files/e2f234bd..80014873

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=12241&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=12241&range=02-03

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/12241.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/12241/head:pull/12241

PR: https://git.openjdk.org/jdk/pull/12241