Interstitial options are not OR'd properly.

Instead of bitwise ORing the interstitial options, we were simply
assigning new values. This CL changes the assignment to a proper bitwise
OR so all options are maintained.

R=meacer@chromium.org,
TBR=jam@chromium.org,creis@chromium.org
BUG=415256

Review URL: https://codereview.chromium.org/578373002

Cr-Commit-Position: refs/heads/master@{#295807}

chrome/browser/chrome_content_browser_client.cc

@@ -1712,11 +1712,11 @@ void ChromeContentBrowserClient::AllowCertificateError(
   // ownership of ssl_blocking_page.
   int options_mask = 0;
   if (overridable)
-    options_mask = SSLBlockingPage::OVERRIDABLE;
+    options_mask |= SSLBlockingPage::OVERRIDABLE;
   if (strict_enforcement)
-    options_mask = SSLBlockingPage::STRICT_ENFORCEMENT;
+    options_mask |= SSLBlockingPage::STRICT_ENFORCEMENT;
   if (expired_previous_decision)
-    options_mask = SSLBlockingPage::EXPIRED_BUT_PREVIOUSLY_ALLOWED;
+    options_mask |= SSLBlockingPage::EXPIRED_BUT_PREVIOUSLY_ALLOWED;
   SSLBlockingPage* ssl_blocking_page = new SSLBlockingPage(
       tab, cert_error, ssl_info, request_url, options_mask, callback);
   ssl_blocking_page->Show();

chrome/browser/ui/webui/interstitials/interstitial_ui.cc

@@ -76,9 +76,9 @@ SSLBlockingPage* CreateSSLBlockingPage(content::WebContents* web_contents) {
   // This delegate doesn't create an interstitial.
   int options_mask = 0;
   if (overridable)
-    options_mask = SSLBlockingPage::OVERRIDABLE;
+    options_mask |= SSLBlockingPage::OVERRIDABLE;
   if (strict_enforcement)
-    options_mask = SSLBlockingPage::STRICT_ENFORCEMENT;
+    options_mask |= SSLBlockingPage::STRICT_ENFORCEMENT;
   return new SSLBlockingPage(web_contents,
                              cert_error,
                              ssl_info,