ambient: update unittest delay

Token refresh unitest has a delay that's too long. It causes many
screen refreshes and makes the unittest run very slow.

R=wutao@chromium.org

Bug: None
Change-Id: Ic93fdc6a97a4125dff42be077d99ca197cc94b3a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2327273Reviewed-by: Tao Wu <wutao@chromium.org>
Commit-Queue: Xiaohui Chen <xiaohuic@chromium.org>
Cr-Commit-Position: refs/heads/master@{#792890}

ash/ambient/ambient_controller_unittest.cc

@@ -22,13 +22,6 @@
 
 namespace ash {
 
-namespace {
-
-constexpr base::TimeDelta kDefaultTokenExpirationDelay =
-    base::TimeDelta::FromHours(1);
-
-}  // namespace
-
 using AmbientControllerTest = AmbientAshTestBase;
 
 TEST_F(AmbientControllerTest, ShowAmbientScreenUponLock) {
@@ -133,9 +126,10 @@ TEST_F(AmbientControllerTest, ShouldRefreshAccessTokenAfterFailure) {
   EXPECT_FALSE(IsAccessTokenRequestPending());
 
   // Token request automatically retry.
-  // The failure delay has jitter so fast forward a bit more, but before
-  // the returned token would expire again.
-  task_environment()->FastForwardBy(kDefaultTokenExpirationDelay / 2);
+  // The failure delay has jitter so fast forward a bit more.
+  constexpr base::TimeDelta kMaxTokenRefreshDelay =
+      base::TimeDelta::FromSeconds(60);
+  task_environment()->FastForwardBy(kMaxTokenRefreshDelay * 2);
   EXPECT_TRUE(IsAccessTokenRequestPending());
 
   // Clean up.