"Starting java language server" processing stops before 100% on workspaces with a non-existing project directory (causing "Classpath is incomplete")

The following workspace opens ok and "starting java language server" process finishes at 100%

{
	"folders": [
        {
            "path":"simple-project1"
        },
        {
            "path":"other-existing-dir"
        }
    ]
}

However the one below one stops at 30% because the first project path in the workspace does not exist. This causes also the following error when clicking on the code of Main.java: "Classpath is incomplete: Only syntax errors will be reported":

{
	"folders": [
        {
            "path":"non-existing-dir"
        },    
        {
            "path":"simple-project1"
        },
        {
            "path":"other-existing-dir"
        }
    ]
}

Environment

• Operating System: Ubuntu 18.04.3 LTS
• JDK version: 13
• Visual Studio Code version: 1.42.1
• Java extension version: 0.57.0 (got from changelog)

Steps To Reproduce

• First open working-workspace.code-workspace and see the thumbs-up symbol on down-right side.
• Then open problematic-workspace.code-workspace and see the thumbs-down symbol on down-right side.

Current Result

Expected Result

Additional Informations

code-missing-project-path-issue.tar.gz

まず code-missing-project-path-issue.tar.gz を展開し、VS Code で working-workspace.code-workspace と problematic-workspace.code-workspace を開きます。最初に、存在しないプロジェクトパスで language server の起動を再現し、その後、進捗と診断を動作する workspace と比較します。起動が 100% に達し、Main.java が不完全な classpath を報告しなくなれば完了です。