Prepare to add more initiator info to CachedResource(Request)

Source/core/loader/cache/CachedResourceLoader.h

Index: Source/core/loader/cache/CachedResourceLoader.h
diff --git a/Source/core/loader/cache/CachedResourceLoader.h b/Source/core/loader/cache/CachedResourceLoader.h
index 728836e769463976a460ac2e6d13f34813600263..f956b9ee110e5dcf6691de877a043e0d710bab4a 100644
--- a/Source/core/loader/cache/CachedResourceLoader.h
+++ b/Source/core/loader/cache/CachedResourceLoader.h
@@ -29,6 +29,7 @@
 #include "core/loader/cache/CachePolicy.h"
 #include "core/loader/cache/CachedResource.h"
 #include "core/loader/cache/CachedResourceHandle.h"
+#include "core/loader/cache/CachedResourceInitiatorInfo.h"
 #include "core/loader/cache/CachedResourceRequest.h"
 #include "core/platform/Timer.h"
 #include "core/platform/network/ResourceLoadPriority.h"
@@ -172,12 +173,6 @@ private:
 
     Timer<CachedResourceLoader> m_garbageCollectDocumentResourcesTimer;
 
-    struct InitiatorInfo {
-        AtomicString name;
-        double startTime;
-    };
-    HashMap<CachedResource*, InitiatorInfo> m_initiatorMap;
-
     // 29 bits left
     bool m_autoLoadImages : 1;
     bool m_imagesEnabled : 1;