PLT-5012 Combine updateLastViewedAt, setLastViewedAt and setActiveChannel into a single API (#4840)

* Combine updateLastViewedAt, setLastViewedAt and setActiveChannel into a single API

* Remove preference DB writes

api/deprecated_test.go

@@ -41,3 +41,44 @@ func TestGetMoreChannel(t *testing.T) {
 		t.Fatal("cache should be empty")
 	}
 }
+
+/*
+func TestSetActiveChannel(t *testing.T) {
+	th := Setup().InitBasic()
+	Client := th.BasicClient
+
+	if _, err := Client.SetActiveChannel(th.BasicChannel.Id); err != nil {
+		t.Fatal(err)
+	}
+
+	status, _ := GetStatus(th.BasicUser.Id)
+	if status.ActiveChannel != th.BasicChannel.Id {
+		t.Fatal("active channel should be set")
+	}
+
+	if _, err := Client.SetActiveChannel(""); err != nil {
+		t.Fatal(err)
+	}
+
+	status, _ = GetStatus(th.BasicUser.Id)
+	if status.ActiveChannel != "" {
+		t.Fatal("active channel should be blank")
+	}
+
+	if _, err := Client.SetActiveChannel("123456789012345678901234567890"); err == nil {
+		t.Fatal("should have failed, id too long")
+	}
+
+	if _, err := Client.UpdateLastViewedAt(th.BasicChannel.Id, true); err != nil {
+		t.Fatal(err)
+	}
+
+	time.Sleep(500 * time.Millisecond)
+
+	status, _ = GetStatus(th.BasicUser.Id)
+	 need to check if offline to catch race
+	if status.Status != model.STATUS_OFFLINE && status.ActiveChannel != th.BasicChannel.Id {
+		t.Fatal("active channel should be set")
+	}
+}
+*/