[Signin][Android] Remove ChromeSigninController from PassphraseActivityTest

Removes ChromeSigninController assert from PassphraseActivityTest. This
assert was verifying that addAndSignInTestAccount succeeded, which is
already ensured in SigninTestUtil.signIn.

Bug: 1046412
Change-Id: Ib54efe5bbe3eb7434cdea161514d48f97387562c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2316083Reviewed-by: Alice Wang <aliceywang@chromium.org>
Commit-Queue: Boris Sazonov <bsazonov@chromium.org>
Cr-Commit-Position: refs/heads/master@{#792829}

chrome/android/javatests/src/org/chromium/chrome/browser/sync/ui/PassphraseActivityTest.java

@@ -25,7 +25,6 @@ import org.chromium.base.test.util.Feature;
 import org.chromium.chrome.browser.sync.FakeProfileSyncService;
 import org.chromium.chrome.browser.sync.ProfileSyncService;
 import org.chromium.chrome.test.ChromeBrowserTestRule;
-import org.chromium.components.signin.ChromeSigninController;
 import org.chromium.content_public.browser.test.util.TestThreadUtils;
 
 /**
@@ -60,9 +59,6 @@ public class PassphraseActivityTest {
         overrideProfileSyncService();
         mChromeBrowserTestRule.addAndSignInTestAccount();
 
-        // PassphraseActivity won't start if an account isn't set.
-        Assert.assertNotNull(ChromeSigninController.get().getSignedInAccountName());
-
         // Create the activity.
         final PassphraseActivity activity = launchPassphraseActivity();
         Assert.assertNotNull(activity);