Remove dead content sniffing code

Source/core/fetch/ResourceLoaderOptions.h

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 19 matching lines @@
 
 #ifndef ResourceLoaderOptions_h
 #define ResourceLoaderOptions_h
 
 #include "core/fetch/FetchInitiatorInfo.h"
 #include "platform/CrossThreadCopier.h"
 #include "platform/weborigin/SecurityOrigin.h"
 
 namespace blink {
 
-enum ContentSniffingPolicy {
-    SniffContent,
-    DoNotSniffContent
-};
-
 enum DataBufferingPolicy {
     BufferData,
     DoNotBufferData
 };
 
 enum ContentSecurityPolicyCheck {
     CheckContentSecurityPolicy,
     DoNotCheckContentSecurityPolicy
 };
 
@@ skipping 30 matching lines @@
 
 // A resource fetch can be marked as being CORS enabled. The loader
 // must perform an access check upon seeing the response.
 enum CORSEnabled {
     NotCORSEnabled,
     IsCORSEnabled
 };
 
 struct ResourceLoaderOptions {
     ResourceLoaderOptions()
-        : sniffContent(DoNotSniffContent)
-        , dataBufferingPolicy(BufferData)
+        : dataBufferingPolicy(BufferData)
         , allowCredentials(DoNotAllowStoredCredentials)
         , credentialsRequested(ClientDidNotRequestCredentials)
         , contentSecurityPolicyOption(CheckContentSecurityPolicy)
         , requestInitiatorContext(DocumentContext)
         , mixedContentBlockingTreatment(TreatAsDefaultForType)
         , synchronousPolicy(RequestAsynchronously)
         , corsEnabled(NotCORSEnabled)
     {
     }
 
     ResourceLoaderOptions(
-        ContentSniffingPolicy sniffContent,
         DataBufferingPolicy dataBufferingPolicy,
         StoredCredentials allowCredentials,
         CredentialRequest credentialsRequested,
         ContentSecurityPolicyCheck contentSecurityPolicyOption,
         RequestInitiatorContext requestInitiatorContext)
-        : sniffContent(sniffContent)
-        , dataBufferingPolicy(dataBufferingPolicy)
+        : dataBufferingPolicy(dataBufferingPolicy)
         , allowCredentials(allowCredentials)
         , credentialsRequested(credentialsRequested)
         , contentSecurityPolicyOption(contentSecurityPolicyOption)
         , requestInitiatorContext(requestInitiatorContext)
         , mixedContentBlockingTreatment(TreatAsDefaultForType)
         , synchronousPolicy(RequestAsynchronously)
         , corsEnabled(NotCORSEnabled)
     {
     }
 
     // Answers the question "can a separate request with these
     // different options be re-used" (e.g. preload request)
     // The safe (but possibly slow) answer is always false.
     bool canReuseRequest(const ResourceLoaderOptions& other) const
     {
-        // sniffContent is dead code.
         // dataBufferingPolicy differences are believed to be safe for re-use.
         // FIXME: check allowCredentials.
         // FIXME: check credentialsRequested.
         // FIXME: check contentSecurityPolicyOption.
         // initiatorInfo is purely informational and should be benign for re-use.
         // requestInitiatorContext is benign (indicates document vs. worker)
         // FIXME: check mixedContentBlockingTreatment.
         // synchronousPolicy (safe to re-use an async XHR response for sync, etc.)
         return corsEnabled == other.corsEnabled;
         // securityOrigin has more complicated checks which callers are responsible for.
     }
 
     // When adding members, CrossThreadResourceLoaderOptionsData should be
     // updated.
-    ContentSniffingPolicy sniffContent; // FIXME: Dead code, please remove.
     DataBufferingPolicy dataBufferingPolicy;
     StoredCredentials allowCredentials; // Whether HTTP credentials and cookies are sent with the request.
     CredentialRequest credentialsRequested; // Whether the client (e.g. XHR) wanted credentials in the first place.
     ContentSecurityPolicyCheck contentSecurityPolicyOption;
     FetchInitiatorInfo initiatorInfo;
     RequestInitiatorContext requestInitiatorContext;
     MixedContentBlockingTreatment mixedContentBlockingTreatment;
     SynchronousPolicy synchronousPolicy;
     CORSEnabled corsEnabled; // If the resource is loaded out-of-origin, whether or not to use CORS.
     RefPtr<SecurityOrigin> securityOrigin;
 };
 
 // Encode AtomicString (in FetchInitiatorInfo) as String to cross threads.
 struct CrossThreadResourceLoaderOptionsData {
     explicit CrossThreadResourceLoaderOptionsData(const ResourceLoaderOptions& options)
-        : sniffContent(options.sniffContent)
-        , dataBufferingPolicy(options.dataBufferingPolicy)
+        : dataBufferingPolicy(options.dataBufferingPolicy)
         , allowCredentials(options.allowCredentials)
         , credentialsRequested(options.credentialsRequested)
         , contentSecurityPolicyOption(options.contentSecurityPolicyOption)
         , initiatorInfo(options.initiatorInfo)
         , requestInitiatorContext(options.requestInitiatorContext)
         , mixedContentBlockingTreatment(options.mixedContentBlockingTreatment)
         , synchronousPolicy(options.synchronousPolicy)
         , corsEnabled(options.corsEnabled)
         , securityOrigin(options.securityOrigin) { }
 
     operator ResourceLoaderOptions() const
     {
         ResourceLoaderOptions options;
-        options.sniffContent = sniffContent;
         options.dataBufferingPolicy = dataBufferingPolicy;
         options.allowCredentials = allowCredentials;
         options.credentialsRequested = credentialsRequested;
         options.contentSecurityPolicyOption = contentSecurityPolicyOption;
         options.initiatorInfo = initiatorInfo;
         options.requestInitiatorContext = requestInitiatorContext;
         options.mixedContentBlockingTreatment = mixedContentBlockingTreatment;
         options.synchronousPolicy = synchronousPolicy;
         options.corsEnabled = corsEnabled;
         options.securityOrigin = securityOrigin;
         return options;
     }
 
-    ContentSniffingPolicy sniffContent;
     DataBufferingPolicy dataBufferingPolicy;
     StoredCredentials allowCredentials;
     CredentialRequest credentialsRequested;
     ContentSecurityPolicyCheck contentSecurityPolicyOption;
     CrossThreadFetchInitiatorInfoData initiatorInfo;
     RequestInitiatorContext requestInitiatorContext;
     MixedContentBlockingTreatment mixedContentBlockingTreatment;
     SynchronousPolicy synchronousPolicy;
     CORSEnabled corsEnabled;
     RefPtr<SecurityOrigin> securityOrigin;
 };
 
 template<> struct CrossThreadCopierBase<false, false, false, ResourceLoaderOptions> {
     typedef CrossThreadResourceLoaderOptionsData Type;
     static Type copy(const ResourceLoaderOptions& options)
     {
         return CrossThreadResourceLoaderOptionsData(options);
     }
 };
 
 } // namespace blink
 
 #endif // ResourceLoaderOptions_h