signin: force web signin flow initiated visits to accounts.google.com to their own process.

chrome/browser/ui/webui/sync_promo/sync_promo_ui.cc

Index: chrome/browser/ui/webui/sync_promo/sync_promo_ui.cc
diff --git a/chrome/browser/ui/webui/sync_promo/sync_promo_ui.cc b/chrome/browser/ui/webui/sync_promo/sync_promo_ui.cc
index 4c0920d235cedc0c7b9665202be3ad1614aaa0b5..5652239f461a19138054a0fbb36a040f05f07c1f 100644
--- a/chrome/browser/ui/webui/sync_promo/sync_promo_ui.cc
+++ b/chrome/browser/ui/webui/sync_promo/sync_promo_ui.cc
@@ -96,6 +96,11 @@ content::WebUIDataSource* CreateSyncUIHTMLSource(content::WebUI* web_ui) {
 
 }  // namespace
 
+// Under the covers, we use a dummy chrome-extension to serve the purposes

[Charlie Reis, 2013/03/06 00:14:54]

nit: chrome-extension URL
(We don't have an actual extension object for it, which is what it sounds like
in the comment.)

[tim (not reviewing), 2013/03/06 01:04:08]

Done.

+// outlined in the .h file comment for this string.
+const char* SyncPromoUI::kChromeSigninEffectiveURL =
+    "chrome-extension://acfccoigjajmmgbhpfbjnpckhjjegnih";
+
 SyncPromoUI::SyncPromoUI(content::WebUI* web_ui) : WebUIController(web_ui) {
   SyncPromoHandler* handler = new SyncPromoHandler(
       g_browser_process->profile_manager());
@@ -259,6 +264,18 @@ GURL SyncPromoUI::GetSyncPromoURL(const GURL& next_page,
 }
 
 // static
+bool SyncPromoUI::IsWebBasedSigninFlowURL(const GURL& url) {
+  if (url == GURL(kChromeSigninEffectiveURL))

[Charlie Reis, 2013/03/06 00:14:54]

You should check the scheme and host.

[tim (not reviewing), 2013/03/06 01:04:08]

Done.

+    return true;
+
+  GURL service_login(GaiaUrls::GetInstance()->service_login_url());
+  if (url.GetOrigin() != service_login.GetOrigin())
+    return false;
+
+  return url.path() == service_login.path();
+}
+
+// static
 GURL SyncPromoUI::GetNextPageURLForSyncPromoURL(const GURL& url) {
   const char* key_name = UseWebBasedSigninFlow() ? kSyncPromoQueryKeyContinue :
       kSyncPromoQueryKeyNextPage;