Fix DEPS for removed directory

Directory components/signin/core/common was removed but still mentioned
in several DEPS files.

Bug: 
Change-Id: Ie1ab30ed38463e84953a8f98108e7ac7e19041cb
Reviewed-on: https://chromium-review.googlesource.com/807904Reviewed-by: Vaclav Brozek <vabr@chromium.org>
Commit-Queue: Alexander Yashkin <a-v-y@yandex-team.ru>
Cr-Commit-Position: refs/heads/master@{#522047}

components/autofill/core/browser/DEPS

@@ -7,7 +7,6 @@ include_rules = [
   "+components/policy",
   "+components/security_state",
   "+components/signin/core/browser",
-  "+components/signin/core/common",
   "+components/sync",
   "+components/variations",
   "+components/version_info",

components/password_manager/sync/browser/DEPS

@@ -2,7 +2,6 @@ include_rules = [
   "+components/keyed_service/core",
   "+components/pref_registry",
   "+components/signin/core/browser",
-  "+components/signin/core/common",
   "+components/sync/base",
   "+components/sync/driver",
   "+components/sync/engine",