Poll Omaha every 5 hours on Brillo builds.

This simple patch pings Omaha every 5 hours in Brillo instead of the 45
minutes we use in Chrome OS.

All Omaha clients except for Chrome OS, ping every 5 hours so we want
Brillo to do the same as all other devices. For Chrome OS, being offline
is more common so we want to check more often.

Bug: 24341710
Test: Deployed on a device. Policy manager logs says it will check in 5h.

Change-Id: Idc363080f6f60274d66cd372a420be9ac8b4ba08
diff --git a/update_manager/chromeos_policy.cc b/update_manager/chromeos_policy.cc
index 1c77318..886ec06 100644
--- a/update_manager/chromeos_policy.cc
+++ b/update_manager/chromeos_policy.cc
@@ -164,7 +164,15 @@
 namespace chromeos_update_manager {
 
 const int ChromeOSPolicy::kTimeoutInitialInterval =  7 * 60;
+
+// TODO(deymo): Split the update_manager policies for Brillo and ChromeOS and
+// make the update check periodic interval configurable.
+#ifdef __ANDROID__
+const int ChromeOSPolicy::kTimeoutPeriodicInterval = 5 * 60 * 60;
+#else
 const int ChromeOSPolicy::kTimeoutPeriodicInterval = 45 * 60;
+#endif  // __ANDROID__
+
 const int ChromeOSPolicy::kTimeoutMaxBackoffInterval = 4 * 60 * 60;
 const int ChromeOSPolicy::kTimeoutRegularFuzz = 10 * 60;
 const int ChromeOSPolicy::kAttemptBackoffMaxIntervalInDays = 16;