[LSP] initialized seems to be sent too eagerly

[mickaelistria]

In the integration with Eclipse IDE, in automated tests (when things go crazy fast), we're hit by the fact that the Omnisharp-Roslyn language server sends initilized too early without being ready to handle requests.
The symptom is that we wait to receive initialized before sending other requests, but if we send them just after, those requests seem ignored.
This sequence of messages is the hint I take to conclude (maybe erroneously) that initialized is sent too early

> {"jsonrpc":"2.0","id":"1","method":"initialize","params":{"processId":15628,"rootPath":"/home/mistria/junit-workspace/csproj_org.eclipse.acute.tests.TestLSPIntegration_1531293766800/","rootUri":"file:///home/mistria/junit-workspace/csproj_org.eclipse.acute.tests.TestLSPIntegration_1531293766800/","capabilities":{"workspace":{"applyEdit":true,"symbol":{},"executeCommand":{"dynamicRegistration":true},"workspaceFolders":true},"textDocument":{"synchronization":{"willSave":true,"willSaveWaitUntil":true,"didSave":true},"completion":{"completionItem":{"snippetSupport":true}},"hover":{},"signatureHelp":{},"references":{},"documentHighlight":{},"documentSymbol":{},"formatting":{},"rangeFormatting":{},"definition":{},"codeAction":{},"codeLens":{},"documentLink":{},"rename":{}}},"clientName":"Eclipse IDE","trace":"off"}}< {"protocolVersion":"2.0","method":"window/logMessage","params":{"type":4,"message":"Starting server..."}

< {"protocolVersion":"2.0","method":"window/logMessage","params":{"type":4,"message":"Added handlers... waiting for initialize..."}}

< {"protocolVersion":"2.0","id":"1","result":{"capabilities":{"textDocumentSync":{"openClose":true,"change":2,"willSave":false,"willSaveWaitUntil":false,"save":{"includeText":true}},"hoverProvider":true,"completionProvider":{"resolveProvider":false},"signatureHelpProvider":{},"definitionProvider":true,"referencesProvider":false,"documentHighlightProvider":false,"documentSymbolProvider":true,"workspaceSymbolProvider":false,"codeActionProvider":false,"documentFormattingProvider":false,"documentRangeFormattingProvider":false,"renameProvider":true,"experimental":{}}}}

> {"jsonrpc":"2.0","method":"initialized","params":{}}

< {"protocolVersion":"2.0","method":"window/logMessage","params":{"type":4,"message":"[dbug]: OmniSharp.Extensions.LanguageServer.LspRequestRouter\n        Finding descriptor for initialized"}}

> {"jsonrpc":"2.0","method":"textDocument/didOpen","params":{"textDocument":{"uri":"file:///home/mistria/junit-workspace/csproj_org.eclipse.acute.tests.TestLSPIntegration_1531293766800/Program.cs","languageId":"cs","version":1,"text":"using System;\r\n\r\nnamespace ConsoleDotNet\r\n{\r\n    class Program\r\n    {\r\n        static void Main(string[] args)\r\n        {\r\n\t\t\tint n \u003d 4;\r\n\t\t\tn++;\r\n            Console.WriteLine(\"Hello World!\" + n);\r\n        }\r\n    }\r\n}\r\n"}}}

< {"protocolVersion":"2.0","method":"window/logMessage","params":{"type":4,"message":"[dbug]: OmniSharp.Extensions.LanguageServer.LspRequestRouter\n        Finding descriptor for textDocument/didOpen"}}

< {"protocolVersion":"2.0","method":"window/logMessage","params":{"type":4,"message":"[trce]: OmniSharp.Extensions.LanguageServer.LspRequestRouter\n        Created attribute cs::file:///home/mistria/junit-workspace/csproj_org.eclipse.acute.tests.TestLSPIntegration_1531293766800/Program.cs"}}

< {"protocolVersion":"2.0","method":"window/logMessage","params":{"type":4,"message":"[trce]: OmniSharp.Extensions.LanguageServer.LspRequestRouter\n        Looking for handler for method textDocument/didOpen"}}

< {"protocolVersion":"2.0","method":"window/logMessage","params":{"type":4,"message":"[trce]: OmniSharp.Extensions.LanguageServer.LspRequestRouter\n        Checking handler textDocument/didOpen:OmniSharp.LanguageServerProtocol.Handlers.TextDocumentSyncHandler"}}

< {"protocolVersion":"2.0","method":"window/logMessage","params":{"type":4,"message":"[trce]: OmniSharp.Extensions.LanguageServer.LspRequestRouter\n        Registration options OmniSharp.Extensions.LanguageServer.Models.TextDocumentRegistrationOptions"}}

< {"protocolVersion":"2.0","method":"window/logMessage","params":{"type":4,"message":"[trce]: OmniSharp.Extensions.LanguageServer.LspRequestRouter\n        Document Selector [**/*.cake]"}}

< {"protocolVersion":"2.0","method":"window/logMessage","params":{"type":4,"message":"[trce]: OmniSharp.Extensions.LanguageServer.LspRequestRouter\n        Checking handler textDocument/didOpen:OmniSharp.LanguageServerProtocol.Handlers.TextDocumentSyncHandler"}}

< {"protocolVersion":"2.0","method":"window/logMessage","params":{"type":4,"message":"[trce]: OmniSharp.Extensions.LanguageServer.LspRequestRouter\n        Registration options OmniSharp.Extensions.LanguageServer.Models.TextDocumentRegistrationOptions"}}

< {"protocolVersion":"2.0","method":"window/logMessage","params":{"type":4,"message":"[trce]: OmniSharp.Extensions.LanguageServer.LspRequestRouter\n        Document Selector [**/*.cs], [**/*.csx]"}}

< {"protocolVersion":"2.0","method":"window/logMessage","params":{"type":4,"message":"[trce]: OmniSharp.Extensions.LanguageServer.LspRequestRouter\n        Handler Selected: OmniSharp.LanguageServerProtocol.Handlers.TextDocumentSyncHandler via [**/*.cs], [**/*.csx] (targeting System.RuntimeType)"}}

< {"protocolVersion":"2.0","method":"window/logMessage","params":{"type":4,"message":"initialized..."}}

As you can see the {"protocolVersion":"2.0","method":"window/logMessage","params":{"type":4,"message":"initialized..."}} comes later while the client (according to the spec) expect initialization to be complete after 1st response.
For some operations like documentChange, it makes that messages can be sent between the declared readiness and the actual readiness, making the server ignore those messages and building an erroneous state of the document.