PushMessaging.UnregistrationReason UMA should count GCM Store resets

content/public/common/push_messaging_status.h

Index: content/public/common/push_messaging_status.h
diff --git a/content/public/common/push_messaging_status.h b/content/public/common/push_messaging_status.h
index d8d7e7e1089724eefc0466b900dfb25fa696f3b0..1a2e7682871818bc622628650f1300c031c56650 100644
--- a/content/public/common/push_messaging_status.h
+++ b/content/public/common/push_messaging_status.h
@@ -90,13 +90,15 @@ enum PushUnregistrationReason {
   // Automatic - incoming message's service worker was not found.
   PUSH_UNREGISTRATION_REASON_DELIVERY_NO_SERVICE_WORKER = 5,
 
+  // Automatic - GCM Store reset due to corruption.
+  PUSH_UNREGISTRATION_REASON_GCM_STORE_RESET = 6,
+
   // NOTE: Do not renumber these as that would confuse interpretation of
   // previously logged data. When making changes, also update the enum list
   // in tools/metrics/histograms/histograms.xml to keep it in sync, and
   // update PUSH_UNREGISTRATION_REASON_LAST below.
 
-  PUSH_UNREGISTRATION_REASON_LAST =
-      PUSH_UNREGISTRATION_REASON_DELIVERY_NO_SERVICE_WORKER
+  PUSH_UNREGISTRATION_REASON_LAST = PUSH_UNREGISTRATION_REASON_GCM_STORE_RESET
 };
 
 // Push unregistration success/error codes for internal use & reporting in UMA.