Fixed CaptivePortal UMA histogram names to be consistent with XML description.

chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc

Index: chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc
diff --git a/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc b/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc
index 1468aa54d3872d3b5543e4c4b63e9c4493a66a2b..f8d8b871cceccad9f12f5dc41f7b3739a2214d9e 100644
--- a/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc
+++ b/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc
@@ -202,17 +202,17 @@ void RecordDiscrepancyWithShill(
     const NetworkPortalDetector::CaptivePortalStatus status) {
   if (network->online()) {
     UMA_HISTOGRAM_ENUMERATION(
-        "CaptivePortal.OOBE.DiscrepancyWithShill.Online",
+        "CaptivePortal.OOBE.DiscrepancyWithShill_Online",
         status,
         NetworkPortalDetector::CAPTIVE_PORTAL_STATUS_COUNT);
   } else if (network->restricted_pool()) {
     UMA_HISTOGRAM_ENUMERATION(
-        "CaptivePortal.OOBE.DiscrepancyWithShill.RestrictedPool",
+        "CaptivePortal.OOBE.DiscrepancyWithShill_RestrictedPool",
         status,
         NetworkPortalDetector::CAPTIVE_PORTAL_STATUS_COUNT);
   } else {
     UMA_HISTOGRAM_ENUMERATION(
-        "CaptivePortal.OOBE.DiscrepancyWithShill.Offline",
+        "CaptivePortal.OOBE.DiscrepancyWithShill_Offline",
         status,
         NetworkPortalDetector::CAPTIVE_PORTAL_STATUS_COUNT);
   }