UX tweaks for CA cert monitoring

- Use a smaller icon on the settings menu in managed device case
- Whitespace/punctuation fix for dialog message string.

Bug: 10421514
Bug: 10785095
Change-Id: Ic7cd0cedd2f7a4075cb9d966265ad40ae002f355

src/com/android/settings/Settings.java

@@ -906,7 +906,7 @@ public class Settings extends PreferenceActivity
                             holder.divider_.setVisibility(View.VISIBLE);
                             boolean isManaged = mDevicePolicyManager.getDeviceOwner() != null;
                             if (isManaged) {
-                                holder.button_.setImageResource(R.drawable.ic_qs_certificate_info);
+                                holder.button_.setImageResource(R.drawable.ic_settings_about);
                             } else {
                                 holder.button_.setImageResource(
                                         android.R.drawable.stat_notify_error);