Pass original int64 response time when caching resource metadata.

Source/core/fetch/ResourceTest.cpp

Index: Source/core/fetch/ResourceTest.cpp
diff --git a/Source/core/fetch/ResourceTest.cpp b/Source/core/fetch/ResourceTest.cpp
index 7173dd41a2068c9890264644c4e403bb64f2b4ab..e37f1dfd1f60369002c88d39d5890147b70e0f80 100644
--- a/Source/core/fetch/ResourceTest.cpp
+++ b/Source/core/fetch/ResourceTest.cpp
@@ -26,7 +26,7 @@ public:
     ~MockPlatform() override { }
 
     // From blink::Platform:
-    void cacheMetadata(const WebURL& url, double, const char*, size_t) override
+    void cacheMetadata(const WebURL& url, int64, const char*, size_t) override
     {
         m_cachedURLs.append(url);
     }