feat(logging): adding more fields to httpRequest (#2663)

diff --git a/logging/logging.go b/logging/logging.go
index 40b8393..7543bb0 100644
--- a/logging/logging.go
+++ b/logging/logging.go
@@ -687,6 +687,12 @@
 	// validated with the origin server before being served from cache. This
 	// field is only meaningful if CacheHit is true.
 	CacheValidatedWithOriginServer bool
+
+	// CacheFillBytes is the number of HTTP response bytes inserted into cache. Set only when a cache fill was attempted.
+	CacheFillBytes int64
+
+	// CacheLookup tells whether or not a cache lookup was attempted.
+	CacheLookup bool
 }
 
 func fromHTTPRequest(r *HTTPRequest) *logtypepb.HttpRequest {
@@ -710,6 +716,9 @@
 		Referer:                        r.Request.Referer(),
 		CacheHit:                       r.CacheHit,
 		CacheValidatedWithOriginServer: r.CacheValidatedWithOriginServer,
+		Protocol:                       r.Request.Proto,
+		CacheFillBytes:                 r.CacheFillBytes,
+		CacheLookup:                    r.CacheLookup,
 	}
 	if r.Latency != 0 {
 		pb.Latency = ptypes.DurationProto(r.Latency)