Choose Go Environment -> Choose from file browser does not work on Windows

[ChrisHines]

What version of Go, VS Code & VS Code Go extension are you using?

• Run go version to get version of Go
  • go version go1.15 windows/amd64
• Run code -v or code-insiders -v to get version of VS Code or VS Code Insiders
  • 1.50.1
• Check your installed extensions to get the version of the VS Code Go extension
  • 0.18.0
• Run go env to get the go development environment details
  • set GO111MODULE=
    set GOARCH=amd64
    set GOBIN=
    set GOCACHE=C:\Users\Chris\AppData\Local\go-build
    set GOENV=C:\Users\Chris\AppData\Roaming\go\env
    set GOEXE=.exe
    set GOFLAGS=
    set GOHOSTARCH=amd64
    set GOHOSTOS=windows
    set GOINSECURE=
    set GOMODCACHE=C:\Users\Chris\Go\pkg\mod
    set GONOPROXY=
    set GONOSUMDB=
    set GOOS=windows
    set GOPATH=C:\Users\Chris\Go
    set GOPRIVATE=
    set GOPROXY=https://proxy.golang.org,direct
    set GOROOT=c:\go
    set GOSUMDB=sum.golang.org
    set GOTMPDIR=
    set GOTOOLDIR=c:\go\pkg\tool\windows_amd64
    set GCCGO=gccgo
    set AR=ar
    set CC=gcc
    set CXX=g++
    set CGO_ENABLED=1
    set GOMOD=
    set CGO_CFLAGS=-g -O2
    set CGO_CPPFLAGS=
    set CGO_CXXFLAGS=-g -O2
    set CGO_FFLAGS=-g -O2
    set CGO_LDFLAGS=-g -O2
    set PKG_CONFIG=pkg-config
    set GOGCCFLAGS=-m64 -mthreads -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=C:\Users\Chris\AppData\Local\Temp\go-build548893822=/tmp/go-build -gno-record-gcc-switches

Share the Go related settings you have added/edited

"go.useLanguageServer": true,
"[go]": {
	"files.eol": "\n", // formatting only supports LF line endings
	"editor.snippetSuggestions": "none",
	"editor.formatOnSave": true,
	"editor.codeActionsOnSave": {
		"source.organizeImports": true
	}
},
"gopls": {
	"usePlaceholders": true, // add parameter placeholders when completing a function
	"hoverKind": "FullDocumentation", // for documentation in completion items
	// Experimental settings
	"staticcheck": true,
},
"go.testFlags": [
	// "-v",
	"-race",
],
"go.coverOnSingleTest": true,
"go.vetOnSave": "off",
"go.buildOnSave": "off",
"go.installDependenciesWhenBuilding": false,
"go.gotoSymbol.includeGoroot": true,
"go.gotoSymbol.includeImports": true,
"go.coverOnSingleTestFile": true,
"go.formatTool": "goimports",
"go.testTimeout": "2m",
"go.coverMode": "atomic",

Describe the bug

On Windows, manually choosing a go.exe command via the Go Status Bar does not work.

Steps to reproduce the behavior:

Navigate in the UI as follows:

1. Click the Go Status Bar
2. Choose Go Environment
3. Choose from file browser
4. Pick any valid go.exe binary

See an error window appear reporting, "/C:/Go/bin/go.exe is not an executable"

[gopherbot]

Change https://golang.org/cl/267898 mentions this issue: src/goEnvironmentStatus: correctly interpret the chosen go path