Do not sniff mime type for fetch() requests

content/browser/loader/mime_sniffing_resource_handler.h

Index: content/browser/loader/mime_sniffing_resource_handler.h
diff --git a/content/browser/loader/mime_sniffing_resource_handler.h b/content/browser/loader/mime_sniffing_resource_handler.h
index 420e4e3f0353c16d16c7bbe3b37ae29fe29204bd..05b901a9c0cb51ca16509e4bc63b6bcf14d8ffca 100644
--- a/content/browser/loader/mime_sniffing_resource_handler.h
+++ b/content/browser/loader/mime_sniffing_resource_handler.h
@@ -13,6 +13,7 @@
 #include "content/browser/loader/layered_resource_handler.h"
 #include "content/common/content_export.h"
 #include "content/public/browser/resource_controller.h"
+#include "content/public/common/request_context_type.h"
 
 namespace net {
 class URLRequest;
@@ -44,7 +45,8 @@ class CONTENT_EXPORT MimeSniffingResourceHandler
                               ResourceDispatcherHostImpl* host,
                               PluginService* plugin_service,
                               InterceptingResourceHandler* intercepting_handler,
-                              net::URLRequest* request);
+                              net::URLRequest* request,
+                              RequestContextType request_context_type);
   ~MimeSniffingResourceHandler() override;
 
  private:
@@ -165,6 +167,8 @@ class CONTENT_EXPORT MimeSniffingResourceHandler
   // needed.
   InterceptingResourceHandler* intercepting_handler_;
 
+  RequestContextType request_context_type_;
+
   base::WeakPtrFactory<MimeSniffingResourceHandler> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(MimeSniffingResourceHandler);