Break chrome_initial's dependence on //components/startup_metric_utils/browser:lib

chrome/app/chrome_main_delegate.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/app/chrome_main_delegate.h"
 
 #include <stddef.h>
 #include <string>
 
 #include "base/base_paths.h"
@@ skipping 416 matching lines @@
   if (process_type.empty()) {
     file_state = logging::DELETE_OLD_LOG_FILE;
   }
   const base::CommandLine& command_line =
       *base::CommandLine::ForCurrentProcess();
   logging::InitChromeLogging(command_line, file_state);
 }
 #endif
 
 #if !defined(CHROME_MULTIPLE_DLL_CHILD)
-void RecordMainStartupMetrics() {
+void RecordMainStartupMetrics(int64_t exe_entry_point_ticks) {

[fdoray, 2016/09/19 17:03:28]

base::TimeTicks

[grt (UTC plus 2), 2016/09/19 19:52:46]

Done.

 #if defined(OS_MACOSX) || defined(OS_WIN) || defined(OS_LINUX)
+  if (exe_entry_point_ticks) {
+    startup_metric_utils::RecordExeMainEntryPointTicks(
+        base::TimeTicks::FromInternalValue(exe_entry_point_ticks));
+  }
   // Record the startup process creation time on supported platforms.
   startup_metric_utils::RecordStartupProcessCreationTime(
       base::CurrentProcessInfo::CreationTime());
 #endif
 
 // On Android the main entry point time is the time when the Java code starts.
 // This happens before the shared library containing this code is even loaded.
 // The Java startup code has recorded that time, but the C++ code can't fetch it
 // from the Java side until it has initialized the JNI. See
 // ChromeMainDelegateAndroid.
 #if !defined(OS_ANDROID)
   startup_metric_utils::RecordMainEntryPointTime(base::Time::Now());
 #endif
 }
 #endif  // !defined(CHROME_MULTIPLE_DLL_CHILD)
 
 }  // namespace
 
-ChromeMainDelegate::ChromeMainDelegate() {
+ChromeMainDelegate::ChromeMainDelegate() : ChromeMainDelegate(0) {}

[brucedawson, 2016/09/16 21:38:39]

I hadn't realized that delegating constructors were approved. Cool.

But, what is the advantage over having a default value for the argument?

[grt (UTC plus 2), 2016/09/17 09:30:05]

Default values for args are somewhat discouraged by the style guide. There's not
a huge difference, I don't think.

+
+ChromeMainDelegate::ChromeMainDelegate(int64_t exe_entry_point_ticks) {
 #if !defined(CHROME_MULTIPLE_DLL_CHILD)
   // Record startup metrics in the browser process. For component builds, there
   // is no way to know the type of process (process command line is not yet
   // initialized), so the function below will also be called in renderers.
   // This doesn't matter as it simply sets global variables.
-  RecordMainStartupMetrics();
+  RecordMainStartupMetrics(exe_entry_point_ticks);
 #endif  // !defined(CHROME_MULTIPLE_DLL_CHILD)
 }
 
 ChromeMainDelegate::~ChromeMainDelegate() {
 }
 
 bool ChromeMainDelegate::BasicStartupComplete(int* exit_code) {
 #if defined(OS_CHROMEOS)
   chromeos::BootTimesRecorder::Get()->SaveChromeMainStats();
 #endif
@@ skipping 578 matching lines @@
     case version_info::Channel::CANARY:
       return true;
     case version_info::Channel::DEV:
     case version_info::Channel::BETA:
     case version_info::Channel::STABLE:
     default:
       // Don't enable instrumentation.
       return false;
   }
 }