Fix broken clockstate.network2 histogram and add unit test

components/ssl_errors/error_classification.h

Index: components/ssl_errors/error_classification.h
diff --git a/components/ssl_errors/error_classification.h b/components/ssl_errors/error_classification.h
index 9bcaeae0475580a0c67e7198b002b1d8a4c16f10..7da66fdd6cf5cd2070f7bc576fbb52bfd9373e4a 100644
--- a/components/ssl_errors/error_classification.h
+++ b/components/ssl_errors/error_classification.h
@@ -46,6 +46,41 @@ enum ClockState {
   CLOCK_STATE_MAX,
 };
 
+// Describes the result of getting network time and if it was
+// unavailable, why it was unavailable. This enum is being histogrammed
+// so do not reorder or remove values.
+//
+// Exposed for testing.
+enum NetworkClockState {
+  // Value 0 was NETWORK_CLOCK_STATE_UNKNOWN_NO_SYNC, which is obsolete
+  // in favor of the finer-grained values below.
+
+  // The clock state relative to network time is unknown because the
+  // user's clock has fallen out of sync with the latest information
+  // from the network (due to e.g. suspend/resume).
+  NETWORK_CLOCK_STATE_UNKNOWN_SYNC_LOST = 1,
+  // The clock is "close enough" to the network time.
+  NETWORK_CLOCK_STATE_OK,
+  // The clock is in the past relative to network time.
+  NETWORK_CLOCK_STATE_CLOCK_IN_PAST,
+  // The clock is in the future relative to network time.
+  NETWORK_CLOCK_STATE_CLOCK_IN_FUTURE,
+  // The clock state relative to network time is unknown because no sync
+  // attempt has been made yet.
+  NETWORK_CLOCK_STATE_UNKNOWN_NO_SYNC_ATTEMPT,
+  // The clock state relative to network time is unknown because one or
+  // more sync attempts has failed.
+  NETWORK_CLOCK_STATE_UNKNOWN_NO_SUCCESSFUL_SYNC,
+  // The clock state relative to network time is unknown because the
+  // first sync attempt is still pending.
+  NETWORK_CLOCK_STATE_UNKNOWN_FIRST_SYNC_PENDING,
+  // The clock state relative to network time is unknown because one or
+  // more time query attempts have failed, and a subsequent sync attempt
+  // is still pending.
+  NETWORK_CLOCK_STATE_UNKNOWN_SUBSEQUENT_SYNC_PENDING,
+  NETWORK_CLOCK_STATE_MAX
+};
+
 // Compares |now_system| to the build time and to the current network time, and
 // returns an inference about the state of the system clock.  A result from
 // network time, if available, will always be preferred to a result from the