Move semantic tokens to LSP implementation

[0dinD]

Requires eclipse-jdtls/eclipse.jdt.ls#1806

This PR simply removes the old client-side code for semantic tokens, which is no longer required when the implementation is moved to LSP in eclipse-jdtls/eclipse.jdt.ls#1806.

I also removed the java.semanticHighlighting.enabled setting, since the extension no longer has control over disabling the semantic tokens provider. But this setting can be substituted with editor.semanticHighlighting.enabled via language-specific editor settings for Java, which should provide the same exact result:

{
    "[java]": {
        "editor.semanticHighlighting.enabled": false
    }
}

Also, I noticed that the wiki page for semantic highlighting is a bit outdated now. Not only is java.semanticHighlighting.enabled not a setting anymore, the prompt to enable or disable semantic highlighting was also removed a while ago. Perhaps it's time to update it? While you're at it, a quick tip is to change the language id for the code block from json to jsonc to get rid of the annoying error highlight on the comments.

[0dinD]

Updated vscode-languageclient to 7.1.0-next.5 to grab microsoft/vscode-languageserver-node@dae62de. For more information, see this comment.

[0dinD]

Not sure why the bot didn't remove the label, because the conflict is fixed now.

OK maybe it just takes a while for it to update.

[Eskibear]

LGTM.

• 7.1.0-next.5 is latest version with several fixes, compared to 7.0.0. And is required to completely resolve flickering issue.
• java.semanticHighlighting.enabled was introduced when semantic highlighting was unstable, allowing users to disable it. Now since vscode have language-specific setting to control it, it's reasonable to directly leverage it.

[Eskibear]

After this PR get merged, we should also update Wiki page.
https://github.com/redhat-developer/vscode-java/wiki/Semantic-Highlighting

[0dinD]

Yes, and also https://github.com/eclipse/eclipse.jdt.ls/wiki/Language-Server-Protocol-support.

I'm also wondering if maybe there should be a wiki page about semantic highlighting in eclipse.jdt.ls as well, now that other clients could start using it over LSP. I was thinking supported token types/modifiers, what they correspond to in Java etc. especially since we have some non-standard ones. The wiki page in this repo could be more VS Code-specific with themeing examples, but also link back to the wiki in eclipse.jdt.ls. What do you think?

It seems like anyone can edit the eclipse.jdt.ls wiki (not sure if that's intentional), so I think I could create a page like that when I have time.

[fbricon]

It seems like anyone can edit the eclipse.jdt.ls wiki (not sure if that's intentional), so I think I could create a page like that when I have time.

It's intentional. Please knock yourself out :-)

[fbricon]

@0dinD thanks!