Add a chrome://interstitials page.

chrome/browser/ssl/ssl_blocking_page.cc

Index: chrome/browser/ssl/ssl_blocking_page.cc
diff --git a/chrome/browser/ssl/ssl_blocking_page.cc b/chrome/browser/ssl/ssl_blocking_page.cc
index ca97c2b60a0a90009235bd3716fc0b3b657f2126..ce532a5023f8cf94f29f236a5ad594956e1da094 100644
--- a/chrome/browser/ssl/ssl_blocking_page.cc
+++ b/chrome/browser/ssl/ssl_blocking_page.cc
@@ -222,6 +222,7 @@ void RecordSSLBlockingPageDetailedStats(
 // No error happening loading a sub-resource triggers an interstitial so far.
 SSLBlockingPage::SSLBlockingPage(
     content::WebContents* web_contents,
+    bool create_interstitial,
     int cert_error,
     const net::SSLInfo& ssl_info,
     const GURL& request_url,
@@ -278,9 +279,15 @@ SSLBlockingPage::SSLBlockingPage(
                  content::Source<Profile>(profile));
 #endif
 
-  interstitial_page_ = InterstitialPage::Create(
-      web_contents_, true, request_url, this);
-  interstitial_page_->Show();
+  // chrome://interstitials page uses this class without actually creating an
+  // interstitial so that it can be debugged. Set |create_interstitial| to true
+  // if the page is going to be used as an actual interstitial and not just part
+  // of the chrome://interstitials webui.
+  if (create_interstitial) {
+    interstitial_page_ = InterstitialPage::Create(
+        web_contents_, true, request_url, this);
+    interstitial_page_->Show();
+  }
 }
 
 SSLBlockingPage::~SSLBlockingPage() {