Add presubmit against usage of deprecated BrowserThreads.

Following announcement @ https://groups.google.com/a/chromium.org/forum/#!topic/chromium-dev/_X8yyHP3uwI

Bug: 653916
Change-Id: I1c6a4dc03adaf45ed8f28554e5d85139e782502a
Reviewed-on: https://chromium-review.googlesource.com/533806
Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Commit-Queue: Gabriel Charette <gab@chromium.org>
Cr-Commit-Position: refs/heads/master@{#479416}

PRESUBMIT.py

@@ -342,6 +342,16 @@
       True,
       (),
     ),
+    (
+      'BrowserThread::(FILE|FILE_USER_BLOCKING|DB|PROCESS_LAUNCHER|CACHE)',
+      (
+        'The non-UI/IO BrowserThreads are deprecated, please migrate this',
+        'code to TaskScheduler. See https://goo.gl/mDSxKl for details.',
+        'For questions, contact base/task_scheduler/OWNERS.',
+      ),
+      True,
+      (),
+    ),
     (
       'base::SequenceChecker',
       (