Add account_id to signin manager notifications.

components/signin/core/browser/signin_manager_base.h

Index: components/signin/core/browser/signin_manager_base.h
diff --git a/components/signin/core/browser/signin_manager_base.h b/components/signin/core/browser/signin_manager_base.h
index 2d3ca43c44746e7df494708c3c6454e0554cee14..a7a0f9b6feba6082e6fa388588334353c9698182 100644
--- a/components/signin/core/browser/signin_manager_base.h
+++ b/components/signin/core/browser/signin_manager_base.h
@@ -48,11 +48,13 @@ class SigninManagerBase : public KeyedService {
     virtual void GoogleSigninFailed(const GoogleServiceAuthError& error) {}
 
     // Called when a user signs into Google services such as sync.
-    virtual void GoogleSigninSucceeded(const std::string& username,
+    virtual void GoogleSigninSucceeded(const std::string& account_id,
+                                       const std::string& username,
                                        const std::string& password) {}
 
     // Called when the currently signed-in user for a user has been signed out.
-    virtual void GoogleSignedOut(const std::string& username) {}
+    virtual void GoogleSignedOut(const std::string& account_id,
+                                 const std::string& username) {}

[guohui, 2014/08/27 17:57:42]

Why have both account_id and username in the signature? account_id is supposed
to uniquely identify a user and it could always be converted to username using
AccountTrackerService when necessary. So isn't it cleaner to have account_id
only?

[Roger Tawa OOO till Jul 10th, 2014/08/27 18:51:01]

Because that would require observers to keep a pointer to the Profile* so that
they could access AccountTrackerService.  In one case that does not happen
(SigninNamesOnIOThread).  Also, I think its better to pass both to the event
than have one come in as an arg and the other have to be fetched from a PKS.

 
    protected:
     virtual ~Observer() {}