RFR: 7480: Trim method descriptor value [v2]

[Gunnar Morling]

> Hey @thegreystone, here's a fix for trimming the method signature value when building the method descriptors in the agent. Without this, wrapping the tags around long signatures like that [will fail](https://github.com/moditect/jfrunit-examples/commit/bd4bc8023c760a3d719dc9295cbe010fb56d7f6f#diff-8999381a163c84127b7e94462f39060c054a984904f82c34713d0ade0954e4c5R81):
> 
> 
>  <descriptor>
>    (Ljava/sql/PreparedStatement;Ljava/lang/Object;ILorg/hibernate/type/descriptor/WrapperOptions;)V
> </descriptor>
> 
> 
> Could you log an issue if you think it's a worthwhile fix? The second commit is some unrelated clean-up I did along the way. Thx!

Gunnar Morling has refreshed the contents of this pull request, and previous commits have been removed. The incremental views will show differences compared to the previous content of the PR. The pull request contains two new commits since the last revision:

 - 7480: Removing unused import and local var
 - 7480: Trimming descriptor

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

Changes:
  - all: https://git.openjdk.java.net/jmc/pull/343/files
  - new: https://git.openjdk.java.net/jmc/pull/343/files/dcf167d0..9243d98b

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jmc&pr=343&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jmc&pr=343&range=00-01

  Stats: 0 lines in 0 files changed: 0 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jmc/pull/343.diff
  Fetch: git fetch https://git.openjdk.java.net/jmc pull/343/head:pull/343

PR: https://git.openjdk.java.net/jmc/pull/343