x/tools/gopls: normalize feature sets of unimported completions and organize imports

[SteelPhase]

What version of Go are you using (go version)?

go version go1.13.4 darwin/amd64

Does this issue reproduce with the latest release?

Can't test on latest release, will update when brew makes go1.13.5 available

What operating system and processor architecture are you using (go env)?

go env Output

GO111MODULE=""
GOARCH="amd64"
GOBIN=""
GOCACHE="/Users/steelphase/Library/Caches/go-build"
GOENV="/Users/steelphase/Library/Application Support/go/env"
GOEXE=""
GOFLAGS=""
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GONOPROXY="go.company.org"
GONOSUMDB="go.company.org"
GOOS="darwin"
GOPATH="/Users/steelphase/Code/Go"
GOPRIVATE="go.company.org"
GOPROXY="https://proxy.golang.org,direct"
GOROOT="/usr/local/Cellar/go/1.13.4/libexec"
GOSUMDB="sum.golang.org"
GOTMPDIR=""
GOTOOLDIR="/usr/local/Cellar/go/1.13.4/libexec/pkg/tool/darwin_amd64"
GCCGO="gccgo"
AR="ar"
CC="clang"
CXX="clang++"
CGO_ENABLED="1"
GOMOD=""
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/0b/zk7t542s1sj_31mwpwyk3cy81gy8z8/T/go-build062639987=/tmp/go-build -gno-record-gcc-switches -fno-common"

What did you do?

Pasted in some code that referenced a dependency that needed to be imported.

What did you expect to see?

import to be autocompleted for direct dependency go.company.org/org/lib/v4/errors

What did you see instead?

import autocompleted to transitive dependency github.com/pkg/errors

Additional Details

This is the go.mod of the module I'm working in

module go.company.org/org/thing

go 1.13

require (
	go.uber.org/zap v1.13.0
	go.company.org/org/lib/v4 v4.1.0
)

output of go mod why

steelphase@macbook:lib$go mod why github.com/pkg/errors
# github.com/pkg/errors
go.company.org/org/thing/cmd/thing
go.uber.org/zap
go.uber.org/zap.test
github.com/pkg/errors

[gopherbot]

Thank you for filing a gopls issue! Please take a look at the Troubleshooting guide, and make sure that you have provided all of the relevant information here.

[SteelPhase]

@gopherbot FeatureRequest

[heschi]

Partly a followup to https://golang.org/cl/204203 -- we should prefer direct deps more than transitive. Also, maybe look into having imports on save do the same sorting.

[gopherbot]

Change https://golang.org/cl/212021 mentions this issue: internal/imports: consider direct mod deps more relevant