RFR: 8256266: Declaration annotations don't work properly for binding variables

[Jan Lahoda]

Basically, javac does not handle code like this properly:

import java.lang.annotation.*;

public class B {
     public void test(Object o) {
         if (o instanceof @A String s) {}
     }
}

@Target(ElementType.LOCAL_VARIABLE)
@interface A {}

The parser needs to allow declaration annotations on binding variables, see:
http://cr.openjdk.java.net/~gbierman/jep394/jep394-20201012/specs/patterns-instanceof-jls.html#jls-14.30.1.1

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

Commit messages:
 - Removing an extra whitespace.
 - 8256266: Declaration annotations don't work properly for binding variables

Changes: https://git.openjdk.java.net/jdk/pull/1192/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=1192&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8256266
  Stats: 201 lines in 6 files changed: 198 ins; 1 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk/pull/1192.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/1192/head:pull/1192

PR: https://git.openjdk.java.net/jdk/pull/1192