Add custom interstitial for captive portals.

chrome/browser/captive_portal/captive_portal_tab_helper.cc

Index: chrome/browser/captive_portal/captive_portal_tab_helper.cc
diff --git a/chrome/browser/captive_portal/captive_portal_tab_helper.cc b/chrome/browser/captive_portal/captive_portal_tab_helper.cc
index d939bdaec5a99cb906a6acea4c9fc02fa199e557..4d4a0aa2a857aabd372c3a318b50177ade4c6654 100644
--- a/chrome/browser/captive_portal/captive_portal_tab_helper.cc
+++ b/chrome/browser/captive_portal/captive_portal_tab_helper.cc
@@ -41,7 +41,7 @@ CaptivePortalTabHelper::CaptivePortalTabHelper(
               profile_,
               web_contents,
               base::Bind(&CaptivePortalTabHelper::OpenLoginTab,
-                         base::Unretained(this)))),
+                         base::Unretained(this), false))),
       login_detector_(new CaptivePortalLoginDetector(profile_)),
       web_contents_(web_contents),
       pending_error_code_(net::OK),
@@ -239,7 +239,7 @@ CaptivePortalTabReloader* CaptivePortalTabHelper::GetTabReloaderForTest() {
   return tab_reloader_.get();
 }
 
-void CaptivePortalTabHelper::OpenLoginTab() {
+void CaptivePortalTabHelper::OpenLoginTab(bool focus) {
   Browser* browser = chrome::FindBrowserWithWebContents(web_contents_);
 
   // If the Profile doesn't have a tabbed browser window open, do nothing.
@@ -255,8 +255,11 @@ void CaptivePortalTabHelper::OpenLoginTab() {
         browser->tab_strip_model()->GetWebContentsAt(i);
     CaptivePortalTabHelper* captive_portal_tab_helper =
         CaptivePortalTabHelper::FromWebContents(web_contents);
-    if (captive_portal_tab_helper->IsLoginTab())
+    if (captive_portal_tab_helper->IsLoginTab()) {
+      if (focus)
+        browser->tab_strip_model()->ActivateTabAt(i, false);
       return;
+    }
   }
 
   // Otherwise, open a login tab.  Only end up here when a captive portal result