PlzNavigate: Move navigation-level mixed content checks to the browser.

content/browser/web_contents/web_contents_impl.h

Index: content/browser/web_contents/web_contents_impl.h
diff --git a/content/browser/web_contents/web_contents_impl.h b/content/browser/web_contents/web_contents_impl.h
index 645cf66c35dc9750709b9de543e0436eb5efe1ee..009a651d15b36cd722c37555c552152fbe0475cb 100644
--- a/content/browser/web_contents/web_contents_impl.h
+++ b/content/browser/web_contents/web_contents_impl.h
@@ -555,6 +555,9 @@ class CONTENT_EXPORT WebContentsImpl
   bool IsOverridingUserAgent() override;
   bool IsJavaScriptDialogShowing() const override;
   bool HideDownloadUI() const override;
+  void DidDisplayInsecureContent() override;
+  void DidRunInsecureContent(const GURL& security_origin,
+                             const GURL& target_url) override;
 
   // NavigatorDelegate ---------------------------------------------------------