Allow fallback from https to http for component update checks.

components/component_updater/default_component_installer.h

Index: components/component_updater/default_component_installer.h
diff --git a/components/component_updater/default_component_installer.h b/components/component_updater/default_component_installer.h
index 5b994915a6bae285a5769bb643b045ae9486e1b3..9de80d6589dc76f566708ab166d7519e08f2c7df 100644
--- a/components/component_updater/default_component_installer.h
+++ b/components/component_updater/default_component_installer.h
@@ -49,6 +49,10 @@ class ComponentInstallerTraits {
   // during component registration from the UI thread.
   virtual bool CanAutoUpdate() const = 0;
 
+  // Returns true if the network communication related to this component
+  // must be encrypted.
+  virtual bool RequiresNetworkEncryption() const = 0;
+
   // OnCustomInstall is called during the installation process. Components that
   // require custom installation operations should implement them here.
   // Returns false if a custom operation failed, and true otherwise.