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

chrome/service/service_utility_process_host.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/service/service_utility_process_host.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/files/file_util.h"
 #include "base/files/scoped_temp_dir.h"
@@ skipping 62 matching lines @@
   SERVICE_UTILITY_DISCONNECTED,
   SERVICE_UTILITY_METAFILE_REQUEST,
   SERVICE_UTILITY_METAFILE_SUCCEEDED,
   SERVICE_UTILITY_METAFILE_FAILED,
   SERVICE_UTILITY_CAPS_REQUEST,
   SERVICE_UTILITY_CAPS_SUCCEEDED,
   SERVICE_UTILITY_CAPS_FAILED,
   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
 
 ServiceUtilityProcessHost::ServiceUtilityProcessHost(
     Client* client, base::MessageLoopProxy* client_message_loop_proxy)
         : handle_(base::kNullProcessHandle),
           client_(client),
           client_message_loop_proxy_(client_message_loop_proxy),
           waiting_for_reply_(false) {
@@ skipping 87 matching lines @@
   cmd_line.AppendSwitchASCII(switches::kProcessType, switches::kUtilityProcess);
   cmd_line.AppendSwitchASCII(switches::kProcessChannelID, channel_id);
   cmd_line.AppendSwitch(switches::kLang);
 
   if (Launch(&cmd_line, no_sandbox, exposed_dir)) {
     UMA_HISTOGRAM_ENUMERATION("CloudPrint.ServiceUtilityProcessHostEvent",
                               SERVICE_UTILITY_STARTED,
                               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;
 }
 
 bool ServiceUtilityProcessHost::Launch(CommandLine* cmd_line,
                                        bool no_sandbox,
                                        const base::FilePath& exposed_dir) {
 #if !defined(OS_WIN)
   // TODO(sanjeevr): Implement for non-Windows OSes.
   NOTIMPLEMENTED();
   return false;
@@ skipping 191 matching lines @@
   if (!metafile.InitFromFile(metafile_path)) {
     OnRenderPDFPagesToMetafileFailed();
   } else {
     OnRenderPDFPagesToMetafileSucceeded(metafile,
                                         highest_rendered_page_number,
                                         scale_factor);
   }
 #endif  // defined(OS_WIN)
 }