Adding instrumentation to locate the source of jankiness.

chrome/common/chrome_version_info_win.cc

Index: chrome/common/chrome_version_info_win.cc
diff --git a/chrome/common/chrome_version_info_win.cc b/chrome/common/chrome_version_info_win.cc
index b52e51e90c6ca493cacf27e183773044f08ff0fe..d692c5e0ac075b18fe1fe27955c916a8d111d5e0 100644
--- a/chrome/common/chrome_version_info_win.cc
+++ b/chrome/common/chrome_version_info_win.cc
@@ -8,6 +8,7 @@
 #include "base/debug/profiler.h"
 #include "base/files/file_path.h"
 #include "base/path_service.h"
+#include "base/profiler/scoped_tracker.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/installer/util/google_update_settings.h"
@@ -17,6 +18,10 @@ namespace chrome {
 
 // static
 std::string VersionInfo::GetVersionStringModifier() {
+  tracked_objects::ScopedTracker tracking_profile(
+      FROM_HERE_WITH_EXPLICIT_FUNCTION(
+          "422460 VersionInfo::GetVersionStringModifier"));
+
 #if defined(GOOGLE_CHROME_BUILD)
   base::FilePath module;
   base::string16 channel;