Do not create base::HighResolutionTimerManager in service utility process

content/utility/utility_main.cc

Index: content/utility/utility_main.cc
diff --git a/content/utility/utility_main.cc b/content/utility/utility_main.cc
index e8acf88ea2b5f98385506762b5ee2662e6a205c0..837e6eeafa69761069acc7ec7ea0be692fafa30e 100644
--- a/content/utility/utility_main.cc
+++ b/content/utility/utility_main.cc
@@ -13,6 +13,7 @@
 #include "content/common/sandbox_linux/sandbox_linux.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/main_function_params.h"
+#include "content/public/common/mojo_channel_switches.h"
 #include "content/public/common/sandbox_init.h"
 #include "content/utility/utility_thread_impl.h"
 
@@ -40,7 +41,18 @@ int UtilityMain(const MainFunctionParams& parameters) {
   ChildProcess utility_process;
   utility_process.set_main_thread(new UtilityThreadImpl());
 
-  base::HighResolutionTimerManager hi_res_timer_manager;
+  // TODO(leonhsl): Both utility process and service utility process would come
+  // here, but the later is launched without connection to service manager.
+  // However, service manager connection is necessary for instantiation of the
+  // process-wide base::PowerMonitor, which is further necessary to
+  // base::HighResolutionTimerManager. So in case of service utility process, we
+  // disable base::HighResolutionTimerManager for now, until we resolved
+  // http://crbug.com/646833.
+  std::unique_ptr<base::HighResolutionTimerManager> hi_res_timer_manager;

[danakj, 2017/01/20 16:37:33]

you could use Optional if u dont want to add malloc just to make this optionally
exist

[leonhsl(Using Gerrit), 2017/01/22 06:05:07]

Done and thanks!

+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(

[danakj, 2017/01/20 16:37:33]

It makes sense that if (!base::PowerMonitor::Get() &&
service_manager_connection_) didn't pass it didn't make a power monitor. But why
is this based on a command line flag and not on if base::PowerMonitor::Get() is
null or not then? It adds additional dependencies to the logic. It would be nice
if this pointed to the ChildThreadImpl code more directly in the comment too,
rather than only through the bug.

[leonhsl(Using Gerrit), 2017/01/22 06:05:07]

Done.

+          switches::kServiceRequestChannelToken)) {
+    hi_res_timer_manager.reset(new base::HighResolutionTimerManager());
+  }
 
 #if defined(OS_WIN)
   bool no_sandbox = parameters.command_line.HasSwitch(switches::kNoSandbox);