Bring back the retry limit to 3.

This reverts r284650. There is one test that is flaky 34% of the time, but that is the exception and not the norm. We don't need 12 retries to make browser_tests or other test suites not flaky. If there are very flaky tests, we should disable them instead. I've disabled all the tests that flake more than 5% of the time.

BUG=395189
R=brettw@chromium.org, sergeyberezin@chromium.org

Review URL: https://codereview.chromium.org/413733003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@285006 0039d316-1c4b-4281-b951-d872f2087c98

base/test/launcher/test_launcher.cc

@@ -343,9 +343,7 @@ TestLauncher::TestLauncher(TestLauncherDelegate* launcher_delegate,
 
     // Enable test retries by default for bots. This can be still overridden
     // from command line using --test-launcher-retry-limit flag.
-    // TODO(sergeyberezin): decrease retry_limit_ back to 3 when the
-    // ignorer_bot is deployed to automatically disable flaky tests.
-    retry_limit_ = 12;
+    retry_limit_ = 3;
   } else {
     // Default to serial test execution if not running on a bot. This makes it
     // possible to disable stdio redirection and can still be overridden with