[cros] OOBE: add histograms for Profile image fetching.

chrome/browser/chromeos/login/user_image_screen.cc

Index: chrome/browser/chromeos/login/user_image_screen.cc
diff --git a/chrome/browser/chromeos/login/user_image_screen.cc b/chrome/browser/chromeos/login/user_image_screen.cc
index e15838222094edc8efa8aaffc737ed49bf023add..fdedafe49216136adc05ac77da5ca66c31c6b90b 100644
--- a/chrome/browser/chromeos/login/user_image_screen.cc
+++ b/chrome/browser/chromeos/login/user_image_screen.cc
@@ -56,6 +56,10 @@ void UserImageScreen::Show() {
   if (!actor_)
     return;
 
+  profile_image_downloader_.reset(new ProfileImageDownloader(this));
+  profile_image_downloader_->Start();
+  profile_image_load_start_time_ = base::Time::Now();

[whywhat, 2011/10/20 16:14:50]

Isn't there a race (in theory) when we download the image faster than the actor
is shown and therefore AddProfileImage in OnDownloadSuccess won't do anything?

[Ivan Korotkov, 2011/10/20 17:13:16]

Hm, right.

+
   actor_->Show();
 
   UserManager* user_manager = UserManager::Get();
@@ -74,9 +78,6 @@ void UserImageScreen::Show() {
   WizardAccessibilityHelper::GetInstance()->MaybeSpeak(
       l10n_util::GetStringUTF8(IDS_OPTIONS_CHANGE_PICTURE_DIALOG_TEXT).c_str(),
       false, false);
-
-  profile_image_downloader_.reset(new ProfileImageDownloader(this));
-  profile_image_downloader_->Start();
 }
 
 void UserImageScreen::Hide() {
@@ -181,6 +182,12 @@ void UserImageScreen::Observe(int type,
 }
 
 void UserImageScreen::OnDownloadSuccess(const SkBitmap& image) {
+  DCHECK(profile_image_load_start_time_.is_null());
+
+  base::TimeDelta delta = base::Time::Now() - profile_image_load_start_time_;
+  VLOG(1) << "Profile image download time: " << delta.InSecondsF();
+  UMA_HISTOGRAM_TIMES("UserImage.FirstTimeProfileImageDownload", delta);
+
   // TODO(avayvod): Check for the default image.
   if (actor_)
     actor_->AddProfileImage(image);