Add certificate error handling to devtools.

content/public/browser/web_contents.h

Index: content/public/browser/web_contents.h
diff --git a/content/public/browser/web_contents.h b/content/public/browser/web_contents.h
index ffcb4b123ec75d027b41a7c68be882daba3ffd19..a7a6cad9352ff771a36cee2be0e5819a57caea90 100644
--- a/content/public/browser/web_contents.h
+++ b/content/public/browser/web_contents.h
@@ -17,6 +17,7 @@
 #include "base/supports_user_data.h"
 #include "build/build_config.h"
 #include "content/common/content_export.h"
+#include "content/public/browser/certificate_request_result_type.h"
 #include "content/public/browser/invalidate_type.h"
 #include "content/public/browser/navigation_controller.h"
 #include "content/public/browser/page_navigator.h"
@@ -432,6 +433,15 @@ class WebContents : public PageNavigator,
   // Invoked when visible security state changes.
   virtual void DidChangeVisibleSecurityState() = 0;
 
+  using CertErrorCallback =
+      base::Callback<void(content::CertificateRequestResultType)>;
+  // Invoked when a certificate error occurs to give observers a chance to
+  // handle the error. The returned value indicates that an observer
+  // will handle the certificate error.
+  virtual bool NotifyCertificateError(int cert_error,
+                                      const GURL& request_url,
+                                      CertErrorCallback handler) = 0;
+
   // Commands ------------------------------------------------------------------
 
   // Stop any pending navigation.