Create LoadProfile method in profile_manager

chrome/browser/profiles/profile_manager.h

Index: chrome/browser/profiles/profile_manager.h
diff --git a/chrome/browser/profiles/profile_manager.h b/chrome/browser/profiles/profile_manager.h
index b4db4fbcb0e3b288c9597ed570d2f79cdad1bcbe..d4aba11966fc94e0fe4f171b05915b7dec30adbc 100644
--- a/chrome/browser/profiles/profile_manager.h
+++ b/chrome/browser/profiles/profile_manager.h
@@ -35,6 +35,7 @@ class ProfileManager : public base::NonThreadSafe,
                        public Profile::Delegate {
  public:
   typedef base::Callback<void(Profile*, Profile::CreateStatus)> CreateCallback;
+  typedef base::Callback<void(Profile*)> ProfileLoadedCallback;
 
   explicit ProfileManager(const base::FilePath& user_data_dir);
   ~ProfileManager() override;
@@ -87,6 +88,15 @@ class ProfileManager : public base::NonThreadSafe,
   // Returns total number of profiles available on this machine.
   size_t GetNumberOfProfiles();
 
+  // Loads an existing profile given it's |profile_name|
+  // The profile is loaded asynchronously and |callback| is executed once it's
+  // loaded
+  // The callback will be executed with a NULL profile if there is an error.
+  // Should be called on the UI thread.

[Peter Beverloo, 2016/03/11 17:45:15]

This should document |incognito| as well, have proper sentences and a few
editorial nits. What about:

  // Asynchronously loads an existing profile given its |profile_name| within
  // the user data directory, optionally in |incognito| mode. The |callback|
  // will be called with the Profile when it has been loaded, or with a nullptr
  // otherwise. Should be called on the UI thread.

[Peter Beverloo, 2016/03/11 17:45:15]

Should we match GetProfile() above and swap out the |profile_name| std::string
with a base::FilePath called |profile_dir|? This would make it easy to have the
same fast-path (GetProfileByPath()) as in that method.

[Miguel Garcia, 2016/03/14 18:29:00]

Done.

[Miguel Garcia, 2016/03/14 18:29:00]

Let's let the owners decide. I am fine swapping it. The difference though is
that in the other methods that is actually the full FilePath whereas here we
want to leave the fact that we are passing the last component of the path as an
implementation detail.

+  void LoadProfile(const std::string& profile_name,
+                   bool incognito,
+                   const ProfileLoadedCallback& callback);
+
   // Explicit asynchronous creation of a profile located at |profile_path|.
   // If the profile has already been created then callback is called
   // immediately. Should be called on the UI thread.