client/web: pipe Server.timeNow() through session funcs

Updates tailscale/corp#14335

Signed-off-by: Sonia Appasamy <sonia@tailscale.com>

client/web/web_test.go

@@ -169,7 +169,10 @@ func TestGetTailscaleBrowserSession(t *testing.T) {
 	defer localapi.Close()
 	go localapi.Serve(lal)
 
-	s := &Server{lc: &tailscale.LocalClient{Dial: lal.Dial}}
+	s := &Server{
+		timeNow: time.Now,
+		lc:      &tailscale.LocalClient{Dial: lal.Dial},
+	}
 
 	// Add some browser sessions to cache state.
 	userASession := &browserSession{
@@ -291,7 +294,7 @@ func TestGetTailscaleBrowserSession(t *testing.T) {
 			if diff := cmp.Diff(session, tt.wantSession); diff != "" {
 				t.Errorf("wrong session; (-got+want):%v", diff)
 			}
-			if gotIsAuthorized := session.isAuthorized(); gotIsAuthorized != tt.wantIsAuthorized {
+			if gotIsAuthorized := session.isAuthorized(s.timeNow()); gotIsAuthorized != tt.wantIsAuthorized {
 				t.Errorf("wrong isAuthorized; want=%v, got=%v", tt.wantIsAuthorized, gotIsAuthorized)
 			}
 		})
@@ -321,6 +324,7 @@ func TestAuthorizeRequest(t *testing.T) {
 	s := &Server{
 		lc:          &tailscale.LocalClient{Dial: lal.Dial},
 		tsDebugMode: "full",
+		timeNow:     time.Now,
 	}
 	validCookie := "ts-cookie"
 	s.browserSessions.Store(validCookie, &browserSession{