Added value to ServiceUtilityProcessHostEventType to track when utility process failed to start.

chrome/service/service_utility_process_host.cc

Index: chrome/service/service_utility_process_host.cc
diff --git a/chrome/service/service_utility_process_host.cc b/chrome/service/service_utility_process_host.cc
index df2cf9400d0302903a1d352a863a383c99ccdc0d..e2d9aa41ed127e454a7400ffc561b14b7a3aa39c 100644
--- a/chrome/service/service_utility_process_host.cc
+++ b/chrome/service/service_utility_process_host.cc
@@ -80,6 +80,7 @@ enum ServiceUtilityProcessHostEvent {
   SERVICE_UTILITY_SEMANTIC_CAPS_REQUEST,
   SERVICE_UTILITY_SEMANTIC_CAPS_SUCCEEDED,
   SERVICE_UTILITY_SEMANTIC_CAPS_FAILED,
+  SERVICE_UTILITY_FAILED_TO_START,
   SERVICE_UTILITY_EVENT_MAX,
 };
 }  // namespace
@@ -187,6 +188,9 @@ bool ServiceUtilityProcessHost::StartProcess(
                               SERVICE_UTILITY_EVENT_MAX);
     return true;
   }
+  UMA_HISTOGRAM_ENUMERATION("CloudPrint.ServiceUtilityProcessHostEvent",
+                            SERVICE_UTILITY_FAILED_TO_START,

[Alexei Svitkine (slow), 2014/09/16 13:17:40]

Can you make a helper function to log this histogram that takes the enum value
as a param?

Each macro expands to a non-trivial amount of code, so doing so will avoid extra
bloat to the binary.

+                            SERVICE_UTILITY_EVENT_MAX);
   return false;
 }