all: rename Kube to Container and IsGCE to IsVM

Once containers run on COS instead of Kubernetes, one name (Kube*) is
wrong and the other (GCE) is ambiguous. So rename them now to be more
specific.

No behavior changes. Just renaming in this step, to reduce size of
next CL.

Updates golang/go#25108

Change-Id: Ib09eb682ef74acbbf6ed50b46074f834ef5e0c0b
Reviewed-on: https://go-review.googlesource.com/111639
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/cmd/coordinator/coordinator.go b/cmd/coordinator/coordinator.go
index 66dafdb..8e9e7c9 100644
--- a/cmd/coordinator/coordinator.go
+++ b/cmd/coordinator/coordinator.go
@@ -473,7 +473,7 @@
 	if buildConf.IsReverse() && !reversePool.CanBuild(buildConf.HostType) {
 		return false
 	}
-	if buildConf.IsKube() && kubeErr != nil {
+	if buildConf.IsContainer() && kubeErr != nil {
 		return false
 	}
 	return true
@@ -1438,9 +1438,9 @@
 		return testPoolHook(conf)
 	}
 	switch {
-	case conf.IsGCE():
+	case conf.IsVM():
 		return gcePool
-	case conf.IsKube():
+	case conf.IsContainer():
 		return kubePool // Kubernetes
 	case conf.IsReverse():
 		return reversePool
diff --git a/cmd/coordinator/kube.go b/cmd/coordinator/kube.go
index 9604db4..fb7be9c 100644
--- a/cmd/coordinator/kube.go
+++ b/cmd/coordinator/kube.go
@@ -207,7 +207,7 @@
 
 func (p *kubeBuildletPool) GetBuildlet(ctx context.Context, hostType string, lg logger) (*buildlet.Client, error) {
 	hconf, ok := dashboard.Hosts[hostType]
-	if !ok || !hconf.IsKube() {
+	if !ok || !hconf.IsContainer() {
 		return nil, fmt.Errorf("kubepool: invalid host type %q", hostType)
 	}
 	if kubeErr != nil {
diff --git a/cmd/debugnewvm/debugnewvm.go b/cmd/debugnewvm/debugnewvm.go
index ff89f6d..a05eb04 100644
--- a/cmd/debugnewvm/debugnewvm.go
+++ b/cmd/debugnewvm/debugnewvm.go
@@ -64,7 +64,7 @@
 	if !ok {
 		log.Fatalf("unknown host type %q", *hostType)
 	}
-	if !hconf.IsGCE() {
+	if !hconf.IsVM() {
 		log.Fatalf("host type %q is not a GCE host type", *hostType)
 	}
 	if *vmImage != "" {
diff --git a/cmd/release/release.go b/cmd/release/release.go
index 7cca33c..381591e 100644
--- a/cmd/release/release.go
+++ b/cmd/release/release.go
@@ -278,7 +278,7 @@
 	}
 
 	var hostArch string // non-empty if we're cross-compiling (s390x)
-	if b.MakeOnly && bc.IsKube() && (bc.GOARCH() != "amd64" && bc.GOARCH() != "386") {
+	if b.MakeOnly && bc.IsContainer() && (bc.GOARCH() != "amd64" && bc.GOARCH() != "386") {
 		hostArch = "amd64"
 	}