This reverts commit 23f69ae958.
Reason for revert: invalid go version '1.15.6': must match format 1.23
Change-Id: Ibe4335f4d9b3ff4b08b4615b91935cca4643ee89
The version in go.mod is used by `go build` to select the version
of the Go language to target. If it is older than the version of Go
in the tree then command line tools like `go test` will give different
results from inside the build. Update the version to match the version
of Go in the tree.
Test: go build ./java
Change-Id: I418f401580be7696e2829c970938c7c82715b932
With this and go1.11beta2, the standard go tools can be used in
build/soong without creating a $GOPATH using something like
setup_go_workspace_for_soong.
Test: go vet android/soong/...
Change-Id: I3c69499b010c8f7f64666208efead4ddb3584b3c