Allow fallback from https to http for component update checks.

components/update_client/utils.cc

Index: components/update_client/utils.cc
diff --git a/components/update_client/utils.cc b/components/update_client/utils.cc
index a76e07329fac74a7c32c71d97fdb4edfd8fe4e9a..caa00cea2073b1cab34ba0dd42df24da940012c4 100644
--- a/components/update_client/utils.cc
+++ b/components/update_client/utils.cc
@@ -34,6 +34,7 @@
 #include "net/url_request/url_fetcher.h"
 #include "net/url_request/url_request_context_getter.h"
 #include "net/url_request/url_request_status.h"
+#include "url/gurl.h"
 
 namespace update_client {
 
@@ -238,4 +239,12 @@ bool IsValidBrand(const std::string& brand) {
          }) == brand.end();
 }
 
+void RemoveUnsecureUrls(std::vector<GURL>* urls) {
+  DCHECK(urls);
+  urls->erase(std::remove_if(
+                  urls->begin(), urls->end(),
+                  [](const GURL& url) { return !url.SchemeIsCryptographic(); }),
+              urls->end());
+}
+
 }  // namespace update_client