vscode-languageclient escapes drive colon on doc URIs on Win

[BoykoAlex]

Does this issue occur when all extensions are disabled?: Yes/No

• VS Code Version: 1.65 (also noted in 1.63)
• OS Version: Win 10 (windows only)

Steps to Reproduce:
Install RedHat Java Language extension to test vscode-languageclient really

1. Set "java.trace.server: "verbose" in the settings.json to see LSP messages that VSCode sends to Java LS
2. Open some Java project in VSCode and then open a Java file
3. Switch on the Output tab and select Language Support for Java in the drop down
4. Examine the LSP messages and note doc URIs that look like: file:///c%3A/Users/sasha/Documents/..., i.e. with escaped drive colon (!?)
5. Search for string symbol. You'd find something like:

[Trace - 12:35:52 PM] Sending request 'textDocument/documentSymbol - (22)'.
Params: {
    "textDocument": {
        "uri": "file:///c%3A/Users/sasha/Documents/workspace-spring-tool-suite-4-4.9.0.RELEASE/spring-petclinic/src/main/java/org/springframework/samples/petclinic/owner/PetRepository.java"
    }
}

In other words the doc URI is sent from the vscode-languageclient with escaped drive colon which is wrong i think. The drive colon should NOT be escaped. This makes Spring Tools language server not to work properly on Windows

[dbaeumer]

@BoykoAlex escaping the colon in drive letters is the default behavior in VS Code. This is why the LSP client for VS Code follows that rule.

However the extension has control over this when creating the LSP client by specifying URI converters. See https://github.com/microsoft/vscode-languageserver-node/blob/5c2e1065493290110bd7c7ea1b10cd6fa08eb81c/client/src/common/client.ts#L684

[dbaeumer]

In the converter function you can simply call uri.toString(true) which will skip these encodings.