Use wait instead of TaskExit.

Signed-off-by: Lantao Liu <lantaol@google.com>

pkg/store/container/container_test.go

@@ -112,7 +112,7 @@ func TestContainerStore(t *testing.T) {
 			ExitCode:   3,
 			Reason:     "TestReason-4a333",
 			Message:    "TestMessage-4a333",
-			Removing:   true,
+			Starting:   true,
 		},
 		"4abcd": {
 			Pid:        4,

pkg/store/container/status.go

@@ -88,6 +88,10 @@ type Status struct {
 	// Human-readable message indicating details about why container is in its
 	// current state.
 	Message string
+	// Starting indicates that the container is in starting state.
+	// This field doesn't need to be checkpointed.
+	// TODO(now): Add unit test.
+	Starting bool `json:"-"`
 	// Removing indicates that the container is in removing state.
 	// This field doesn't need to be checkpointed.
 	Removing bool `json:"-"`

pkg/store/container/status_test.go

@@ -75,6 +75,7 @@ func TestStatusEncodeDecode(t *testing.T) {
 		Reason:     "test-reason",
 		Message:    "test-message",
 		Removing:   true,
+		Starting:   true,
 	}
 	assert := assertlib.New(t)
 	data, err := s.encode()
@@ -82,6 +83,7 @@ func TestStatusEncodeDecode(t *testing.T) {
 	newS := &Status{}
 	assert.NoError(newS.decode(data))
 	s.Removing = false // Removing should not be encoded.
+	s.Starting = false // Starting should not be encoded.
 	assert.Equal(s, newS)
 
 	unsupported, err := json.Marshal(&versionedStatus{