Update prefservice only if it is available.

components/security_interstitials/content/security_interstitial_page.cc

Index: components/security_interstitials/content/security_interstitial_page.cc
diff --git a/components/security_interstitials/content/security_interstitial_page.cc b/components/security_interstitials/content/security_interstitial_page.cc
index 6ff9b3a9ac5a82ac4f91ea2164dcbf8362ed3e07..5f6db08f2906ccd5cf19dd31c61b8140344124b1 100644
--- a/components/security_interstitials/content/security_interstitial_page.cc
+++ b/components/security_interstitials/content/security_interstitial_page.cc
@@ -35,8 +35,10 @@ SecurityInterstitialPage::SecurityInterstitialPage(
       controller_(std::move(controller)) {
   // Determine if any prefs need to be updated prior to showing the security
   // interstitial.
-  safe_browsing::UpdatePrefsBeforeSecurityInterstitial(
-      controller_->GetPrefService());
+  if (controller_->GetPrefService()) {

[meacer, 2017/01/12 23:37:12]

nit: In which cases can this be null? Might be useful to add a comment about
that.

[sgurun-gerrit only, 2017/01/12 23:52:54]

Done.

+    safe_browsing::UpdatePrefsBeforeSecurityInterstitial(
+        controller_->GetPrefService());
+  }
 
   // Creating interstitial_page_ without showing it leaks memory, so don't
   // create it here.
@@ -74,10 +76,6 @@ void SecurityInterstitialPage::Show() {
   AfterShow();
 }
 
-bool SecurityInterstitialPage::IsPrefEnabled(const char* pref) {
-  return controller_->GetPrefService()->GetBoolean(pref);
-}
-
 SecurityInterstitialControllerClient* SecurityInterstitialPage::controller() {
   return controller_.get();
 }