Optimize CT & OCSP handling code

net/cert/ct_objects_extractor.cc

Index: net/cert/ct_objects_extractor.cc
diff --git a/net/cert/ct_objects_extractor.cc b/net/cert/ct_objects_extractor.cc
index 4f451fdd1f21217a783ed2f519acfcf0fd7c440b..1a6e6e4772d63a4dd924e11220ef4b5f934d4a10 100644
--- a/net/cert/ct_objects_extractor.cc
+++ b/net/cert/ct_objects_extractor.cc
@@ -252,7 +252,7 @@ bool GetX509LogEntry(X509Certificate::OSCertHandle leaf, LogEntry* result) {
 
 bool ExtractSCTListFromOCSPResponse(X509Certificate::OSCertHandle issuer,
                                     const std::string& cert_serial_number,
-                                    const std::string& ocsp_response,
+                                    base::StringPiece ocsp_response,
                                     std::string* sct_list) {
   // The input is an OCSPResponse. See RFC2560, section 4.2.1. The SCT list is
   // in the extensions field of the SingleResponse which matches the input