Add chrome/browser/flags to DEPS.

This is a common dependency that should be available to all modules.

TBR=twellington@chromium.org

Bug: 1041468
Change-Id: Idbd04924ced7ee17ebac68b127b2a9d064cf0db2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2015612Reviewed-by: Henrique Nakashima <hnakashima@chromium.org>
Reviewed-by: Theresa  <twellington@chromium.org>
Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>
Cr-Commit-Position: refs/heads/master@{#734279}

chrome/android/DEPS

 include_rules = [
+  "+chrome/browser/flags",
   "+chrome/browser/notifications",
   "+chrome/browser/preferences/android/java",
   "+chrome/browser/settings/android",

chrome/android/java/src/org/chromium/chrome/browser/tab/DEPS

@@ -8,6 +8,7 @@ include_rules = [
   "+chrome/android/java/src/org/chromium/chrome/browser/ssl/SecurityStateModel.java",
   "+chrome/android/java/src/org/chromium/chrome/browser/tab",
   "+chrome/android/java/src/org/chromium/chrome/browser/webapps/WebDisplayMode.java",
+  "+chrome/browser/flags",
   "+chrome/browser/preferences",
   "+chrome/browser/ui/android/native_page",
   "+chrome/browser/ui/android/widget",