Reland "Allow cache reuse of some requests with Cache-Control headers"

Source/platform/network/ResourceRequest.h

Index: Source/platform/network/ResourceRequest.h
diff --git a/Source/platform/network/ResourceRequest.h b/Source/platform/network/ResourceRequest.h
index a9a80c174c3d5cb12f7cf05d80953d9cd340aeec..ad51cd94dc21b9dfc8a13ca31db5e3eb84a71839 100644
--- a/Source/platform/network/ResourceRequest.h
+++ b/Source/platform/network/ResourceRequest.h
@@ -30,6 +30,7 @@
 
 #include "platform/network/FormData.h"
 #include "platform/network/HTTPHeaderMap.h"
+#include "platform/network/HTTPParsers.h"
 #include "platform/network/ResourceLoadPriority.h"
 #include "platform/weborigin/KURL.h"
 #include "platform/weborigin/Referrer.h"
@@ -209,6 +210,10 @@ public:
     TargetType targetType() const { return m_targetType; }
     void setTargetType(TargetType type) { m_targetType = type; }
 
+    bool cacheControlContainsNoCache();
+    bool cacheControlContainsNoStore();
+    bool hasCacheValidatorFields();
+
     static double defaultTimeoutInterval(); // May return 0 when using platform default.
     static void setDefaultTimeoutInterval(double);
 
@@ -238,6 +243,7 @@ private:
     RefPtr<ExtraData> m_extraData;
     TargetType m_targetType;
     ReferrerPolicy m_referrerPolicy;
+    CacheControlHeader m_cacheControlHeader;
 
     static double s_defaultTimeoutInterval;
 };