test_planner: Stop writing the old oneof-style "test_unit" field

The recipe code has already been migrated to the new way.
e.g. no references to "test_unit" here: https://cs.corp.google.com/search/?q=package:%5E(chromeos).*$+f:%5Einfra/recipes+test_unit

BUG=chromium:963016
TEST=unit tests

Change-Id: Id31a919c64516ad1660e0e0c249db9eec60c1d6a
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/infra/test_planner/+/1613772
Reviewed-by: Sean Abraham <seanabraham@chromium.org>
Commit-Queue: Sean Abraham <seanabraham@chromium.org>
Tested-by: Sean Abraham <seanabraham@chromium.org>
diff --git a/deploy_cipd.json b/deploy_cipd.json
index 2c3bf3c..7c00b15 100644
--- a/deploy_cipd.json
+++ b/deploy_cipd.json
@@ -1,6 +1,6 @@
 {
   "result": {
     "package": "chromiumos/infra/test_planner",
-    "instance_id": "-hIcDWKd2u00yTupEaPY3RiTiSpPvYi-ri1Zs87JGZQC"
+    "instance_id": "zzOc81uersYND4eOgxCzhWLpYomu6p0ae0k_FCUjC-AC"
   }
 }
\ No newline at end of file
diff --git a/src/testplans/go.mod b/src/testplans/go.mod
index 293b8e5..115268e 100644
--- a/src/testplans/go.mod
+++ b/src/testplans/go.mod
@@ -15,7 +15,7 @@
 	github.com/smartystreets/assertions v0.0.0-20190401211740-f487f9de1cd3 // indirect
 	github.com/smartystreets/goconvey v0.0.0-20190330032615-68dc04aab96a // indirect
 	github.com/texttheater/golang-levenshtein v0.0.0-20180516184445-d188e65d659e // indirect
-	go.chromium.org/chromiumos/infra/proto/go v0.0.0-20190514225112-82c9d54cbe67
+	go.chromium.org/chromiumos/infra/proto/go v0.0.0-20190516043545-0b3cc740c3cb
 	go.chromium.org/luci v0.0.0-20190404171609-14fb4fbce8ea
 	golang.org/x/oauth2 v0.0.0-20190402181905-9f3314589c9a // indirect
 	google.golang.org/grpc v1.19.1 // indirect
diff --git a/src/testplans/go.sum b/src/testplans/go.sum
index 77326f8..ccbd1d2 100644
--- a/src/testplans/go.sum
+++ b/src/testplans/go.sum
@@ -120,6 +120,7 @@
 go.chromium.org/chromiumos/infra/proto v0.0.0-20190514195506-9aeeb525f8a2 h1:gljjPuw1pRc2lK9PLb6VvGvXgNDOuKCEmHnKlhxHUcg=
 go.chromium.org/chromiumos/infra/proto v0.0.0-20190514223940-f962e75b3f92 h1:qLY0UEyKr26Er3Ilv+7RuRgj5SGWtChdLFztrOxjB6g=
 go.chromium.org/chromiumos/infra/proto v0.0.0-20190514225112-82c9d54cbe67 h1:oF/0U7DfnhRgov+m3xk3u8KC9yrjuKP+VTZ0CWkOOkw=
+go.chromium.org/chromiumos/infra/proto v0.0.0-20190516043545-0b3cc740c3cb h1:sjs4greMgtc8PqFEqVvKMSnDiDivuFq0RGyeZuaSWRs=
 go.chromium.org/chromiumos/infra/proto/go v0.0.0-20190506153826-232eeaaa29a9 h1:87ML72wybRl6dKe4qyvTH5Y6ihvrTxT13+xTsz7F6tE=
 go.chromium.org/chromiumos/infra/proto/go v0.0.0-20190506153826-232eeaaa29a9/go.mod h1:Y1AiM5bpNKKecKy3wgiBwF9q1PJ/f57z86DpkNrMehk=
 go.chromium.org/chromiumos/infra/proto/go v0.0.0-20190514195506-9aeeb525f8a2 h1:kAJWnYFu1Vvk3RdZLKz9rDDBsi4m8WPDXv7r9plSEaY=
@@ -128,6 +129,8 @@
 go.chromium.org/chromiumos/infra/proto/go v0.0.0-20190514223940-f962e75b3f92/go.mod h1:Y1AiM5bpNKKecKy3wgiBwF9q1PJ/f57z86DpkNrMehk=
 go.chromium.org/chromiumos/infra/proto/go v0.0.0-20190514225112-82c9d54cbe67 h1:gTOb9jvLQwIgx+fRhTV1TIUwWoB5SMBdvsZG+0R6/oA=
 go.chromium.org/chromiumos/infra/proto/go v0.0.0-20190514225112-82c9d54cbe67/go.mod h1:Y1AiM5bpNKKecKy3wgiBwF9q1PJ/f57z86DpkNrMehk=
+go.chromium.org/chromiumos/infra/proto/go v0.0.0-20190516043545-0b3cc740c3cb h1:4D0aQ9N/vMdx7Z09a8IZ0UQW4y6Nku1PJAdNnbhDh5s=
+go.chromium.org/chromiumos/infra/proto/go v0.0.0-20190516043545-0b3cc740c3cb/go.mod h1:Y1AiM5bpNKKecKy3wgiBwF9q1PJ/f57z86DpkNrMehk=
 go.chromium.org/luci v0.0.0-20190404171609-14fb4fbce8ea h1:qf3Ri7sv3yJPL4E0iq4hBYn3AFSf2dNNJpuZDBXAT2E=
 go.chromium.org/luci v0.0.0-20190404171609-14fb4fbce8ea/go.mod h1:MIQewVTLvOvc0UioV0JNqTNO/RspKFS0XEeoKrOxsdM=
 go.opencensus.io v0.18.0/go.mod h1:vKdFvxhtzZ9onBp9VKHK8z/sRpBMnKAsufL7wlDrCOA=
diff --git a/src/testplans/internal/generator/generator.go b/src/testplans/internal/generator/generator.go
index d05a0b6..22c949f 100644
--- a/src/testplans/internal/generator/generator.go
+++ b/src/testplans/internal/generator/generator.go
@@ -147,11 +147,6 @@
 			for _, gce := range pttr.GceTestCfg.GceTest {
 				gce.Common = withCritical(gce.Common, critical)
 			}
-			resp.TestUnit = append(resp.TestUnit,
-				&testplans.TestUnit{
-					BuildTarget:  &bt,
-					BuildPayload: bp,
-					TestCfg:      &testplans.TestUnit_GceTestCfg{GceTestCfg: pttr.GceTestCfg}})
 			resp.GceTestUnits = append(resp.GceTestUnits, &testplans.GceTestUnit{
 				Common:     tuc,
 				GceTestCfg: pttr.GceTestCfg})
@@ -163,11 +158,6 @@
 				for _, hw := range pttr.HwTestCfg.HwTest {
 					hw.Common = withCritical(hw.Common, critical)
 				}
-				resp.TestUnit = append(resp.TestUnit,
-					&testplans.TestUnit{
-						BuildTarget:  &bt,
-						BuildPayload: bp,
-						TestCfg:      &testplans.TestUnit_HwTestCfg{HwTestCfg: pttr.HwTestCfg}})
 				resp.HwTestUnits = append(resp.HwTestUnits, &testplans.HwTestUnit{
 					Common:    tuc,
 					HwTestCfg: pttr.HwTestCfg})
@@ -177,11 +167,6 @@
 			for _, moblab := range pttr.MoblabVmTestCfg.MoblabTest {
 				moblab.Common = withCritical(moblab.Common, critical)
 			}
-			resp.TestUnit = append(resp.TestUnit,
-				&testplans.TestUnit{
-					BuildTarget:  &bt,
-					BuildPayload: bp,
-					TestCfg:      &testplans.TestUnit_MoblabVmTestCfg{MoblabVmTestCfg: pttr.MoblabVmTestCfg}})
 			resp.MoblabVmTestUnits = append(resp.MoblabVmTestUnits, &testplans.MoblabVmTestUnit{
 				Common:          tuc,
 				MoblabVmTestCfg: pttr.MoblabVmTestCfg})
@@ -190,11 +175,6 @@
 			for _, tastVm := range pttr.TastVmTestCfg.TastVmTest {
 				tastVm.Common = withCritical(tastVm.Common, critical)
 			}
-			resp.TestUnit = append(resp.TestUnit,
-				&testplans.TestUnit{
-					BuildTarget:  &bt,
-					BuildPayload: bp,
-					TestCfg:      &testplans.TestUnit_TastVmTestCfg{TastVmTestCfg: pttr.TastVmTestCfg}})
 			resp.TastVmTestUnits = append(resp.TastVmTestUnits, &testplans.TastVmTestUnit{
 				Common:        tuc,
 				TastVmTestCfg: pttr.TastVmTestCfg})
@@ -206,11 +186,6 @@
 				for _, vm := range pttr.VmTestCfg.VmTest {
 					vm.Common = withCritical(vm.Common, critical)
 				}
-				resp.TestUnit = append(resp.TestUnit,
-					&testplans.TestUnit{
-						BuildTarget:  &bt,
-						BuildPayload: bp,
-						TestCfg:      &testplans.TestUnit_VmTestCfg{VmTestCfg: pttr.VmTestCfg}})
 				resp.VmTestUnits = append(resp.VmTestUnits, &testplans.VmTestUnit{
 					Common:    tuc,
 					VmTestCfg: pttr.VmTestCfg})
diff --git a/src/testplans/internal/generator/generator_test.go b/src/testplans/internal/generator/generator_test.go
index dbdbe86..bbd34e9 100644
--- a/src/testplans/internal/generator/generator_test.go
+++ b/src/testplans/internal/generator/generator_test.go
@@ -122,43 +122,6 @@
 	}
 
 	expectedTestPlan := &testplans.GenerateTestPlanResponse{
-		TestUnit: []*testplans.TestUnit{
-			{
-				BuildTarget: &chromiumos.BuildTarget{Name: "reef"},
-				TestCfg:     &testplans.TestUnit_GceTestCfg{GceTestCfg: reefGceTestCfg},
-				BuildPayload: &testplans.BuildPayload{
-					ArtifactsGsBucket: GS_BUCKET,
-					ArtifactsGsPath:   GS_PATH_PREFIX + "reef",
-				}},
-			{
-				BuildTarget: &chromiumos.BuildTarget{Name: "reef"},
-				TestCfg:     &testplans.TestUnit_MoblabVmTestCfg{MoblabVmTestCfg: reefMoblabVmTestCfg},
-				BuildPayload: &testplans.BuildPayload{
-					ArtifactsGsBucket: GS_BUCKET,
-					ArtifactsGsPath:   GS_PATH_PREFIX + "reef",
-				}},
-			{
-				BuildTarget: &chromiumos.BuildTarget{Name: "kevin"},
-				TestCfg:     &testplans.TestUnit_HwTestCfg{HwTestCfg: kevinHWTestCfg},
-				BuildPayload: &testplans.BuildPayload{
-					ArtifactsGsBucket: GS_BUCKET,
-					ArtifactsGsPath:   GS_PATH_PREFIX + "kevin",
-				}},
-			{
-				BuildTarget: &chromiumos.BuildTarget{Name: "kevin"},
-				TestCfg:     &testplans.TestUnit_TastVmTestCfg{TastVmTestCfg: kevinTastVMTestCfg},
-				BuildPayload: &testplans.BuildPayload{
-					ArtifactsGsBucket: GS_BUCKET,
-					ArtifactsGsPath:   GS_PATH_PREFIX + "kevin",
-				}},
-			{
-				BuildTarget: &chromiumos.BuildTarget{Name: "kevin"},
-				TestCfg:     &testplans.TestUnit_VmTestCfg{VmTestCfg: kevinVMTestCfg},
-				BuildPayload: &testplans.BuildPayload{
-					ArtifactsGsBucket: GS_BUCKET,
-					ArtifactsGsPath:   GS_PATH_PREFIX + "kevin",
-				}},
-		},
 		GceTestUnits: []*testplans.GceTestUnit{
 			{Common: &testplans.TestUnitCommon{
 				BuildPayload: &testplans.BuildPayload{
@@ -260,15 +223,6 @@
 	}
 
 	expectedTestPlan := &testplans.GenerateTestPlanResponse{
-		TestUnit: []*testplans.TestUnit{
-			{
-				BuildTarget: &chromiumos.BuildTarget{Name: "reef"},
-				TestCfg:     &testplans.TestUnit_GceTestCfg{GceTestCfg: reefGceTestCfg},
-				BuildPayload: &testplans.BuildPayload{
-					ArtifactsGsBucket: GS_BUCKET,
-					ArtifactsGsPath:   GS_PATH_PREFIX + "reef",
-				}},
-		},
 		GceTestUnits: []*testplans.GceTestUnit{
 			{Common: &testplans.TestUnitCommon{
 				BuildPayload: &testplans.BuildPayload{
@@ -325,8 +279,7 @@
 		t.Error(err)
 	}
 
-	expectedTestPlan := &testplans.GenerateTestPlanResponse{
-		TestUnit: []*testplans.TestUnit{}}
+	expectedTestPlan := &testplans.GenerateTestPlanResponse{}
 
 	if diff := cmp.Diff(expectedTestPlan, actualTestPlan, cmpopts.EquateEmpty()); diff != "" {
 		t.Errorf("CreateCombinedTestPlan bad result (-want/+got)\n%s", diff)
@@ -390,8 +343,7 @@
 		t.Error(err)
 	}
 
-	expectedTestPlan := &testplans.GenerateTestPlanResponse{
-		TestUnit: []*testplans.TestUnit{}}
+	expectedTestPlan := &testplans.GenerateTestPlanResponse{}
 
 	if diff := cmp.Diff(expectedTestPlan, actualTestPlan, cmpopts.EquateEmpty()); diff != "" {
 		t.Errorf("CreateCombinedTestPlan bad result (-want/+got)\n%s", diff)
@@ -455,7 +407,6 @@
 	}
 
 	expectedTestPlan := &testplans.GenerateTestPlanResponse{
-		TestUnit:     []*testplans.TestUnit{},
 		GceTestUnits: []*testplans.GceTestUnit{}}
 
 	if diff := cmp.Diff(expectedTestPlan, actualTestPlan, cmpopts.EquateEmpty()); diff != "" {