Webview editorGroupToViewColumn exception

Issue Type: Bug

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Exceptions in console

Invalid group provided: Error: Invalid group provided
    at Object.t.editorGroupToViewColumn (file:///Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/out/vs/workbench/workbench.main.js:2843:274)
    at k.onActiveEditorChanged (file:///Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/out/vs/workbench/workbench.main.js:3592:893)
    at d.fire (file:///Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/out/vs/workbench/workbench.main.js:75:436)
    at e.doEmitActiveEditorChangeEvent (file:///Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/out/vs/workbench/workbench.main.js:4507:68)
    at e.handleActiveEditorChange (file:///Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/out/vs/workbench/workbench.main.js:4506:872)
    at t.push.e.onDidGroupChange.t (file:///Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/out/vs/workbench/workbench.main.js:4507:160)
    at d.fire (file:///Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/out/vs/workbench/workbench.main.js:75:416)
    at t.editorControl.openEditor.then.t (file:///Applications/Visual Studio Code - Insiders.app/Contents/Resources/app/out/vs/workbench/workbench.main.js:5025:915)

https://github.com/Microsoft/vscode/blob/52ec060807443e812290f472f0b550798cb727f3/src/vs/workbench/api/electron-browser/mainThreadWebview.ts#L315

VS Code version: Code - Insiders 1.33.0-insider (1afeb46cc4f2856ed6d0759fff85b13647c7ab83, 2019-03-27T16:02:22.809Z) OS version: Darwin x64 18.2.0

System Info

|Item|Value| |---|---| |CPUs|Intel(R) Core(TM) i7-4770HQ CPU @ 2.20GHz (8 x 2200)| |GPU Status|2d_canvas: enabled
checker_imaging: disabled_off
flash_3d: enabled
flash_stage3d: enabled
flash_stage3d_baseline: enabled
gpu_compositing: enabled
multiple_raster_threads: enabled_on
native_gpu_memory_buffers: enabled
rasterization: enabled
surface_synchronization: enabled_on
video_decode: enabled
webgl: enabled
webgl2: enabled| |Load (avg)|2, 2, 2| |Memory (System)|16.00GB (0.27GB free)| |Process Argv|-psn_0_2204186| |Screen Reader|no| |VM|0%|

Extensions (46)

Extension|Author (truncated)|Version ---|---|--- markdown-emoji|bie|0.0.7 solargraph|cas|0.19.3 npm-intellisense|chr|1.3.0 vscode-svgviewer|css|2.0.0 vscode-markdownlint|Dav|0.25.1 vscode-eslint|dba|1.8.2 xml|Dot|2.4.0 gitlens|eam|9.5.1 remotehub|eam|0.2.0 tsl-problem-matcher|eam|0.0.4 EditorConfig|Edi|0.13.0 tslint|eg2|1.0.43 vscode-npm-script|eg2|0.3.5 vsc-material-theme|Equ|2.8.2 vscode-pull-request-github|Git|0.5.1 ocaml|hac|0.6.43 beautify|Hoo|1.4.11 references-plusplus|jri|0.0.5 graphql-for-vscode|kum|1.13.0 dotenv|mik|1.0.1 theme-monokai-pro-vscode|mon|1.1.12 vscode-azurefunctions|ms-|0.15.0 vscode-language-pack-zh-hans|MS-|1.33.0 python|ms-|2019.3.6139 azure-account|ms-|0.8.0 Go|ms-|0.9.2 PowerShell|ms-|1.11.0 vscode-typescript-tslint-plugin|ms-|1.0.0 wordcount|ms-|0.1.0 vsliveshare|ms-|0.3.1403 debugger-for-chrome|msj|4.11.3 debugger-for-ios-web|msj|0.1.2 color-highlight|nau|2.3.0 vetur|oct|0.17.1 subtitles-editor|pep|1.0.2 vscode-versionlens|pfl|0.22.0 material-icon-theme|PKi|3.7.0 seti-icons|qin|0.1.3 project-snippets|reb|0.5.0 ruby|reb|0.22.3 smartpaste|reb|0.0.3 toggle|reb|0.0.1 sass-indented|rob|1.5.1 rust|rus|0.5.4 sourcekit-lsp|unp|0.0.1 vscode-lldb|vad|1.2.1 (12 theme extensions excluded)

microsoft / vscode

Webview editorGroupToViewColumn exception #71316