Add fhorschig@ and vabr@ to Android passwords settings OWNERS

Bug: None
Change-Id: I72665789d93e1eb0b5fe8ac8920cac8a5e0b2615
Reviewed-on: https://chromium-review.googlesource.com/984873Reviewed-by: Theresa <twellington@chromium.org>
Reviewed-by: Friedrich Horschig <fhorschig@chromium.org>
Commit-Queue: Vaclav Brozek <vabr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#547655}

chrome/android/java/src/org/chromium/chrome/browser/preferences/password/OWNERS

+# For non-UI logic only. For UI, see parent OWNERS file.
+fhorschig@chromium.org
+vabr@chromium.org
+
+# COMPONENT: UI>Browser>Passwords