Add fallback behavior if the last used profile cannot initialize

chrome/browser/ui/startup/startup_browser_creator.cc

Index: chrome/browser/ui/startup/startup_browser_creator.cc
diff --git a/chrome/browser/ui/startup/startup_browser_creator.cc b/chrome/browser/ui/startup/startup_browser_creator.cc
index 8cb76a7171ef019ee311ff43e2587668cccb3051..7f7a64a36b806098bdc1941b8f7f71bebb99a1fd 100644
--- a/chrome/browser/ui/startup/startup_browser_creator.cc
+++ b/chrome/browser/ui/startup/startup_browser_creator.cc
@@ -884,3 +884,79 @@ base::FilePath GetStartupProfilePath(const base::FilePath& user_data_dir,
   return g_browser_process->profile_manager()->GetLastUsedProfileDir(
       user_data_dir);
 }
+
+#if !defined(OS_CHROMEOS) && !defined(OS_ANDROID)
+Profile* GetStartupProfile(const base::FilePath& user_data_dir,
+                           const base::CommandLine& command_line) {
+  ProfileManager* profile_manager = g_browser_process->profile_manager();
+
+  base::FilePath profile_path =
+      GetStartupProfilePath(user_data_dir, command_line);
+  Profile* profile = profile_manager->GetProfile(profile_path);
+
+  // If there is no entry in profile attributes storage, the profile is deleted,
+  // and we should show the user manager. Also, when using
+  // --new-profile-management, if the profile is locked we should show the user
+  // manager as well. When neither of these is true, we can safely start up with
+  // |profile|.
+  auto* storage = &profile_manager->GetProfileAttributesStorage();
+  ProfileAttributesEntry* entry;
+  bool has_entry = storage->GetProfileAttributesWithPath(profile_path, &entry);
+  if (has_entry && (!switches::IsNewProfileManagement() ||
+                    !entry->IsSigninRequired() || !profile)) {
+    return profile;
+  }
+
+  // We want to show the user manager. To indicate this, return the guest
+  // profile. However, we can only do this if the system profile (where the user
+  // manager lives) also exists (or is creatable).
+  return profile_manager->GetProfile(ProfileManager::GetSystemProfilePath()) ?
+         profile_manager->GetProfile(ProfileManager::GetGuestProfilePath()) :
+         nullptr;
+}
+
+Profile* GetFallbackStartupProfile() {
+  ProfileManager* profile_manager = g_browser_process->profile_manager();
+  // The only known reason for profiles to fail initialization is unable to

[Peter Kasting, 2016/07/19 21:56:07]

Nit: unable -> being unable

[WC Leung, 2016/07/27 18:00:06]

Done.

+  // create the profile directory, and this has already happened in
+  // GetStartupProfilePath() before calling this function. In this case,
+  // creation of new profiles is expected to fail. So only existing profiles are
+  // attempted for fallback.
+
+  // If the last used profile is unable to initialize, see if any of other last
+  // opened profiles can initialize successfully.

[Peter Kasting, 2016/07/19 21:56:06]

Nit: "The last used profile could not be initialized, so see if any other last
opened profiles can be initialized successfully."

[WC Leung, 2016/07/27 18:00:05]

Done.

+  std::vector<Profile*> last_opened_profiles =
+      ProfileManager::GetLastOpenedProfiles();
+  auto& storage = profile_manager->GetProfileAttributesStorage();

[Peter Kasting, 2016/07/19 21:56:07]

Nit: Use auto* storage = &...

[WC Leung, 2016/07/27 18:00:05]

Oh my bad... should have done this before. Why I didn't make it in the CL?
Done anyway.

+  for (Profile* last_opened_profile : last_opened_profiles) {

[Peter Kasting, 2016/07/19 21:56:06]

Nit: Avoids extra temp:

  for (Profile* profile : ProfileManager::GetLastOpenedProfiles()) {

[WC Leung, 2016/07/27 18:00:05]

Done.

+    // Return any profile that is not locked.
+    ProfileAttributesEntry* entry;
+    bool has_entry = storage.GetProfileAttributesWithPath(
+                         last_opened_profile->GetPath(), &entry);
+    if (!has_entry || !entry->IsSigninRequired())
+      return last_opened_profile;
+  }
+
+  // If it still fails, try to initialize a guest profile and a system profile.
+  // Show the user manager if this is successful.

[Peter Kasting, 2016/07/19 21:56:07]

Nit: "Couldn't initialize any last opened profiles.  Try to show the user
manager, which requires successful initialization of the guest and system
profiles."

[WC Leung, 2016/07/27 18:00:06]

Done.

+  Profile* guest_profile =
+      profile_manager->GetProfile(ProfileManager::GetGuestProfilePath());
+  Profile* system_profile =
+      profile_manager->GetProfile(ProfileManager::GetSystemProfilePath());
+  if (guest_profile && system_profile)
+    return guest_profile;
+
+  // If still fails, try to open any profile that is not locked.

[Peter Kasting, 2016/07/19 21:56:07]

Nit: "Couldn't show the user manager either.  Try to open..."

[WC Leung, 2016/07/27 18:00:05]

Done.

+  std::vector<ProfileAttributesEntry*> entries =
+      storage.GetAllProfilesAttributes();
+  for (ProfileAttributesEntry* entry : entries) {

[Peter Kasting, 2016/07/19 21:56:07]

Nit: Avoids extra temp:

  for (ProfileAttributesEntry* entry : storage.GetAllProfilesAttributes()) {

[WC Leung, 2016/07/27 18:00:05]

Done.

+    if (!entry->IsSigninRequired()) {
+      Profile* profile = profile_manager->GetProfile(entry->GetPath());
+      if (profile)
+        return profile;
+    }
+  }
+
+  return nullptr;
+}
+#endif  // !defined(OS_CHROMEOS) && !defined(OS_ANDROID)