win/clang: Try to fix build after https://codereview.chromium.org/1243293003

chrome/browser/safe_browsing/incident_reporting/platform_state_store.cc

Index: chrome/browser/safe_browsing/incident_reporting/platform_state_store.cc
diff --git a/chrome/browser/safe_browsing/incident_reporting/platform_state_store.cc b/chrome/browser/safe_browsing/incident_reporting/platform_state_store.cc
index 0c657c6587918a955a5a2fda6a55777df1d73bc4..7c666c7f154059b93f23baba8f251753607a3db2 100644
--- a/chrome/browser/safe_browsing/incident_reporting/platform_state_store.cc
+++ b/chrome/browser/safe_browsing/incident_reporting/platform_state_store.cc
@@ -149,6 +149,9 @@ scoped_ptr<base::DictionaryValue> Load(Profile* profile) {
       // Return null for all error cases.
       value_dict.reset();
       break;
+    case PlatformStateStoreLoadResult::NUM_RESULTS:
+      NOTREACHED();
+      break;
   }
   UMA_HISTOGRAM_ENUMERATION(
       "SBIRS.PSSLoadResult", static_cast<uint32_t>(result),