Implement a poor man's PostAfterStartupTask() function.

chrome/browser/chrome_content_browser_client.cc

Index: chrome/browser/chrome_content_browser_client.cc
diff --git a/chrome/browser/chrome_content_browser_client.cc b/chrome/browser/chrome_content_browser_client.cc
index c1869b95dda65db5509a7ef1cfb658d66c109f6e..26923555bb20825fb7c7b904cc817a49f10c2071 100644
--- a/chrome/browser/chrome_content_browser_client.cc
+++ b/chrome/browser/chrome_content_browser_client.cc
@@ -19,6 +19,7 @@
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/threading/sequenced_worker_pool.h"
+#include "chrome/browser/after_startup_task.h"
 #include "chrome/browser/browser_about_handler.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/browser_shutdown.h"
@@ -789,6 +790,13 @@ content::BrowserMainParts* ChromeContentBrowserClient::CreateBrowserMainParts(
   return main_parts;
 }
 
+void ChromeContentBrowserClient::PostAfterStartupTask(
+    const tracked_objects::Location& from_here,
+    const scoped_refptr<base::TaskRunner>& task_runner,
+    const base::Closure& task) {
+  ::PostAfterStartupTask(from_here, task_runner, task);
+}
+
 std::string ChromeContentBrowserClient::GetStoragePartitionIdForSite(
     content::BrowserContext* browser_context,
     const GURL& site) {