SafeBrowsing: allow WebView to customize the Help Center URL

chrome/browser/safe_browsing/safe_browsing_blocking_page.cc

Index: chrome/browser/safe_browsing/safe_browsing_blocking_page.cc
diff --git a/chrome/browser/safe_browsing/safe_browsing_blocking_page.cc b/chrome/browser/safe_browsing/safe_browsing_blocking_page.cc
index e866451be644bf46324dc2ba87f76d9be972c403..091be51d806f8fb5de624158c6d653f959a4910d 100644
--- a/chrome/browser/safe_browsing/safe_browsing_blocking_page.cc
+++ b/chrome/browser/safe_browsing/safe_browsing_blocking_page.cc
@@ -76,7 +76,8 @@ class SafeBrowsingBlockingPageFactoryImpl
         web_contents->GetBrowserContext()->IsOffTheRecord(),
         IsExtendedReportingEnabled(*prefs), IsScout(*prefs),
         is_proceed_anyway_disabled,
-        BaseBlockingPage::IsMainPageLoadBlocked(unsafe_resources));
+        BaseBlockingPage::IsMainPageLoadBlocked(unsafe_resources),
+        nullptr);

[Jialiu Lin, 2017/05/17 15:47:46]

nit:  some in-line comment will be helpful. e.g. 

nullptr /* default help article link */);

[felt, 2017/05/17 15:55:50]

I'd prefer to have Chrome pass in the default link instead of nullptr. It seems
less prone to error. Could we do that instead?

[Nate Fischer, 2017/05/17 22:34:43]

Sure, I went with Felt's suggestion

 
     return new SafeBrowsingBlockingPage(ui_manager, web_contents,
                                         main_frame_url, unsafe_resources,