Add support for transparent/translucent pixels in the user image

chrome/browser/chromeos/login/screens/user_image_screen.cc

Index: chrome/browser/chromeos/login/screens/user_image_screen.cc
diff --git a/chrome/browser/chromeos/login/screens/user_image_screen.cc b/chrome/browser/chromeos/login/screens/user_image_screen.cc
index 3c52e2132153b45866742ad96e4c958ccdf60da2..d0d6e834a829c0d936eda389126ae78a503e96a4 100644
--- a/chrome/browser/chromeos/login/screens/user_image_screen.cc
+++ b/chrome/browser/chromeos/login/screens/user_image_screen.cc
@@ -193,8 +193,8 @@ void UserImageScreen::OnImageAccepted() {
         accept_photo_after_decoding_ = true;
         return;
       }
-      image_manager->SaveUserImage(
-          user_manager::UserImage::CreateAndEncode(user_photo_));
+      image_manager->SaveUserImage(user_manager::UserImage::CreateAndEncode(
+          user_photo_, user_manager::UserImage::FORMAT_JPEG));
       uma_index = default_user_image::kHistogramImageFromCamera;
       break;
     case user_manager::User::USER_IMAGE_PROFILE: