Fuzz also over IntegrityFeatures flag.

Increases fuzzer coverage to match changes in cl 924187. Hopefully also
fixes the referenced bug, because this now explicitly initializes
CachedDocumentParameters::integrity_features when called from the fuzzer.

Bug: 818396
Change-Id: Ica18606543bd5cb36df567a132a6fe2b1da9620f
Reviewed-on: https://chromium-review.googlesource.com/968508
Commit-Queue: Daniel Vogelheim <vogelheim@chromium.org>
Reviewed-by: Charlie Harrison <csharrison@chromium.org>
Reviewed-by: Max Moroz <mmoroz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#544030}

third_party/WebKit/Source/core/html/parser/HTMLPreloadScannerFuzzer.cpp

@@ -8,6 +8,7 @@
 #include "core/html/parser/ResourcePreloader.h"
 #include "core/html/parser/TextResourceDecoderForFuzzing.h"
 #include "core/media_type_names.h"
+#include "platform/loader/SubresourceIntegrity.h"
 #include "platform/testing/BlinkFuzzerTestSupport.h"
 #include "platform/testing/FuzzedDataProvider.h"
 
@@ -23,6 +24,10 @@ std::unique_ptr<CachedDocumentParameters> CachedDocumentParametersForFuzzing(
   document_parameters->viewport_meta_zero_values_quirk =
       fuzzed_data.ConsumeBool();
   document_parameters->viewport_meta_enabled = fuzzed_data.ConsumeBool();
+  document_parameters->integrity_features =
+      fuzzed_data.ConsumeBool()
+          ? SubresourceIntegrity::IntegrityFeatures::kDefault
+          : SubresourceIntegrity::IntegrityFeatures::kSignatures;
   return document_parameters;
 }