Implement a poor man's PostAfterStartupTask() function.

content/browser/browser_main_runner.cc

Index: content/browser/browser_main_runner.cc
diff --git a/content/browser/browser_main_runner.cc b/content/browser/browser_main_runner.cc
index b12ccd6da25c855ea0f831d2373e63d9ff04261f..38c235521828c49a1730ae81f1b170967cafed1e 100644
--- a/content/browser/browser_main_runner.cc
+++ b/content/browser/browser_main_runner.cc
@@ -10,6 +10,7 @@
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/statistics_recorder.h"
+#include "base/time/time.h"
 #include "base/trace_event/trace_event.h"
 #include "content/browser/browser_main_loop.h"
 #include "content/browser/browser_shutdown_profile_dumper.h"
@@ -111,6 +112,8 @@ void InstallSha256LegacyHooks() {
 #endif  // _WIN64
 }
 
+base::TimeTicks g_process_startup_ticks;
+
 }  // namespace
 
 #endif  // OS_WIN
@@ -134,6 +137,8 @@ class BrowserMainRunnerImpl : public BrowserMainRunner {
     if (!initialization_started_) {
       initialization_started_ = true;
 
+    g_process_startup_ticks = base::TimeTicks::Now();
+
 #if !defined(OS_IOS)
       if (parameters.command_line.HasSwitch(switches::kWaitForDebugger))
         base::debug::WaitForDebugger(60, true);
@@ -283,4 +288,10 @@ BrowserMainRunner* BrowserMainRunner::Create() {
   return new BrowserMainRunnerImpl();
 }
 
+// TODO(michaeln): Where should this go and what signal should be used?
+bool IsBrowserStartingUp() {

[michaeln, 2015/02/24 23:07:11]

The startup metrics component tracks some stats like this, but it's
interpretation of 'starting up' is just how long till the main msg loop begins
pumping msgs.

+  return base::TimeTicks::Now() - g_process_startup_ticks <
+         base::TimeDelta::FromSeconds(15);
+}
+
 }  // namespace content