Export a private webstore API to call into the new inline sign-in flow.

chrome/browser/extensions/api/webstore_private/webstore_private_api.cc

Index: chrome/browser/extensions/api/webstore_private/webstore_private_api.cc
diff --git a/chrome/browser/extensions/api/webstore_private/webstore_private_api.cc b/chrome/browser/extensions/api/webstore_private/webstore_private_api.cc
index 15a5f04c4c782077609fb5293d378bae7d7dd638..ed1337f7d553e4c8de2a582ceca451998e93424e 100644
--- a/chrome/browser/extensions/api/webstore_private/webstore_private_api.cc
+++ b/chrome/browser/extensions/api/webstore_private/webstore_private_api.cc
@@ -30,6 +30,8 @@
 #include "chrome/browser/ui/app_list/app_list_service.h"
 #include "chrome/browser/ui/app_list/app_list_util.h"
 #include "chrome/browser/ui/browser.h"
+#include "chrome/browser/ui/webui/signin/login_ui_service.h"
+#include "chrome/browser/ui/webui/signin/login_ui_service_factory.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "chrome/common/extensions/extension_l10n_util.h"
 #include "chrome/common/pref_names.h"
@@ -58,6 +60,7 @@ namespace GetStoreLogin = api::webstore_private::GetStoreLogin;
 namespace GetWebGLStatus = api::webstore_private::GetWebGLStatus;
 namespace InstallBundle = api::webstore_private::InstallBundle;
 namespace IsInIncognitoMode = api::webstore_private::IsInIncognitoMode;
+namespace SignIn = api::webstore_private::SignIn;
 namespace SetStoreLogin = api::webstore_private::SetStoreLogin;
 
 namespace {
@@ -686,4 +689,37 @@ bool WebstorePrivateIsInIncognitoModeFunction::RunImpl() {
   return true;
 }
 
+bool WebstorePrivateSignInFunction::RunImpl() {

[Ilya Sherman, 2014/03/12 06:34:29]

Hui, this CL is not nearly ready for a full review, but could you please take a
look at this method and let me know if it looks like I'm on the right track?

[guohui, 2014/03/12 18:17:39]

it looks good in general, plz see my comments below.

+  scoped_ptr<SignIn::Params> params = SignIn::Params::Create(*args_);
+  EXTENSION_FUNCTION_VALIDATE(params);
+
+  // The |continue_url| is required.
+  if (!params->continue_url)
+    return false;
+
+  // If sign-in is disallowed, give up.
+  SigninManagerBase* signin_manager =
+      SigninManagerFactory::GetForProfile(GetProfile());
+  if (!signin_manager || !signin_manager->IsSigninAllowed())
+    return false;

[Ilya Sherman, 2014/03/12 06:34:29]

Am I right to be using a SigninManager here?

[guohui, 2014/03/12 18:17:39]

yes, i think so, though i think you need to notify the webstore of the failure
through a callback, so that webstore could handle different cases properly.

+
+  // If the user is already signed in, there's nothing else to do.
+  if (!signin_manager->GetAuthenticatedUsername().empty())
+    return true;

[Ilya Sherman, 2014/03/12 06:34:29]

Is it appropriate to bail if the user is already signed in?

[guohui, 2014/03/12 18:17:39]

yup, again we should notify the webstore of the result via a callback.

+
+  // TODO(isherman): What to do if an authentication is already in progress?
+  // if (signin_manager->AuthInProgress()) ...

[Ilya Sherman, 2014/03/12 06:34:29]

What's the expected behavior if there is already an authentication in progress? 
Incidentally, does "AuthInProgress()" returning |true| mean that there is a
sign-in page open, or that the user has submitted data through a sign-in page,
but the server hasn't yet replied?

[guohui, 2014/03/12 18:17:39]

this means signin is already triggered through a sign-in page, but not finished
yet, since signin is a multi-step process involving multiple calls to Gaia and
sync server thus it could take a few seconds or more. The simplest solution is
to just return a status code via callback.

+
+  // TODO(isherman): Replace the current tab with the UI, rather than showing it
+  // in a new tab.

[Ilya Sherman, 2014/03/12 06:34:29]

Are you aware of existing code that I can re-use to do this, or do I likely need
to build some plumbing here to enable this functionality?

[guohui, 2014/03/12 18:17:39]

hmm i think you could simply navigate the current tab to the signin URL, see
example at 
https://code.google.com/p/chromium/codesearch#chromium/src/chrome/browser/ui/...

+  // TODO(isherman): Make use of the |continue_url|.
+  LoginUIService* login_ui_service =
+      LoginUIServiceFactory::GetForProfile(GetProfile());
+  login_ui_service->ShowLoginPopup();

[Ilya Sherman, 2014/03/12 06:34:29]

Is a LoginUIService the best way to show an inline weblogin page hosted on the
chrome:// protocol?

[guohui, 2014/03/12 18:17:39]

LoginUIService::ShowLoginPopup shows the login UI in a singleton tab, thus i
don't think we should use it here.

+
+  // TODO(isherman): Just for debugging:
+  DLOG(WARNING) << *params->continue_url;
+  return true;
+}
+
 }  // namespace extensions