Revert of Disable flaky test...

Revert of Disable flaky test org.chromium.chrome.browser.webapps.WebApkUpdateManagerTest#testCanonicalUrlsDif… (patchset #1 id:1 of https://codereview.chromium.org/2571773002/ )

Reason for revert:
reenabling, see bug

Original issue's description:
> Disable flaky test org.chromium.chrome.browser.webapps.WebApkUpdateManagerTest#testCanonicalUrlsDifferentShouldUpgrade.
>
> TBR=miguelg@chromium.org
>
> BUG=673385
>
> Committed: https://crrev.com/44ff0871ca857e221a227306f7c256bf5e66659a
> Cr-Commit-Position: refs/heads/master@{#438120}

TBR=miguelg@chromium.org,grunell@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=673385

Review-Url: https://codereview.chromium.org/2574583004
Cr-Commit-Position: refs/heads/master@{#438586}

chrome/android/javatests/src/org/chromium/chrome/browser/webapps/WebApkUpdateManagerTest.java

@@ -10,7 +10,6 @@ import android.test.suitebuilder.annotation.MediumTest;
 import org.chromium.base.ThreadUtils;
 import org.chromium.base.test.util.CallbackHelper;
 import org.chromium.base.test.util.CommandLineFlags;
-import org.chromium.base.test.util.DisabledTest;
 import org.chromium.base.test.util.Feature;
 import org.chromium.blink_public.platform.WebDisplayMode;
 import org.chromium.chrome.browser.ChromeSwitches;
@@ -187,7 +186,6 @@ public class WebApkUpdateManagerTest extends ChromeTabbedActivityTestBase {
      */
     @MediumTest
     @Feature({"WebApk"})
-    @DisabledTest(message = "crbug.com/673385")
     public void testCanonicalUrlsDifferentShouldUpgrade() throws Exception {
         // URL canonicalization should replace "%62" with 'b'.
         CreationData creationData = defaultCreationData(mTestServer);