AI 144953: Provide UI for push mode accounts.
  1.  Generalize the code for the various spinners that control
  account check frequency.
  2.  Provide an API for looking up store attributes (and refactor
  existing instatiateStore logic to use it).
  3.  Cleanup the old code that was used to setup frequency spinners.
  4.  Hardwire Exchange accounts to default into push mode.
  Notes to tester:
  1.  For each account type (POP, IMAP, EAS) we need to check that
  auto & manual creation "do the right thing" for frequencies.
  POP & IMAP should offer "none" or time intervals, while EAS
  should offer "push", "none", or time intervals.
  2.  EAS accounts should default to "push", all others to "15 min"
  3.  Make sure that you can edit existing account settings and see
  the right choices (only EAS should be offered push).
  4.  I couldn't write an automated test for the mail checker service,
  please confirm that POP & IMAP accounts are checked at the right
  intervals (or never, if set for "none".)
  BUG=1776149

Automated import of CL 144953
diff --git a/res/values/strings.xml b/res/values/strings.xml
index 47dffdc..a7d8da2 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -310,6 +310,8 @@
     <string name="account_setup_options_mail_check_frequency_label">Email checking frequency</string>
     <!-- In Account setup options & Account Settings screens, label for email check frequency option -->
     <string name="account_setup_options_mail_check_frequency_never">Never</string>
+    <!-- In Account setup options & Account Settings screens, label for email check frequency option -->
+    <string name="account_setup_options_mail_check_frequency_push">Automatic (Push)</string>
     <!-- In Account setup options & Account Settings screens, email check frequency option -->
     <string name="account_setup_options_mail_check_frequency_5min">Every 5 minutes</string>
     <!-- In Account setup options & Account Settings screens, email check frequency option -->