CSP: Adding the 'upgrade-insecure-requests' directive.

Source/core/fetch/ResourceFetcher.h

Index: Source/core/fetch/ResourceFetcher.h
diff --git a/Source/core/fetch/ResourceFetcher.h b/Source/core/fetch/ResourceFetcher.h
index fa580ed6700e972e934f1b6111adaee6f5e08140..0f075cc24215de7d5627fb685249012a1c19537b 100644
--- a/Source/core/fetch/ResourceFetcher.h
+++ b/Source/core/fetch/ResourceFetcher.h
@@ -171,6 +171,8 @@ public:
     String getCacheIdentifier() const;
 
 private:
+    friend class ResourceFetcherTest;
+
     explicit ResourceFetcher(DocumentLoader*);
 
     bool shouldLoadNewResource(Resource::Type) const;
@@ -188,6 +190,7 @@ private:
     void determineRequestContext(ResourceRequest&, Resource::Type);
     ResourceRequestCachePolicy resourceRequestCachePolicy(const ResourceRequest&, Resource::Type);
     void addAdditionalRequestHeaders(ResourceRequest&, Resource::Type);
+    void maybeUpgradeInsecureRequestURL(FetchRequest&);
 
     bool canRequest(Resource::Type, const ResourceRequest&, const KURL&, const ResourceLoaderOptions&, bool forPreload, FetchRequest::OriginRestriction) const;