Introduce AsyncDocumentSubresourceFilter.

components/test_runner/mock_web_document_subresource_filter.cc

Index: components/test_runner/mock_web_document_subresource_filter.cc
diff --git a/components/test_runner/mock_web_document_subresource_filter.cc b/components/test_runner/mock_web_document_subresource_filter.cc
index c8397eec6f48b9798ee44933d04d67b2aa8cbdec..43d0c001c87f33269953947a79f4a39518d20561 100644
--- a/components/test_runner/mock_web_document_subresource_filter.cc
+++ b/components/test_runner/mock_web_document_subresource_filter.cc
@@ -18,7 +18,7 @@ MockWebDocumentSubresourceFilter::MockWebDocumentSubresourceFilter(
 
 MockWebDocumentSubresourceFilter::~MockWebDocumentSubresourceFilter() {}
 
-blink::WebDocumentSubresourceFilter::LoadPolicy
+blink::WebDocumentSubresourceFilterLoadPolicy
 MockWebDocumentSubresourceFilter::getLoadPolicy(
     const blink::WebURL& resource_url,
     blink::WebURLRequest::RequestContext /* ignored */) {
@@ -29,8 +29,8 @@ MockWebDocumentSubresourceFilter::getLoadPolicy(
                         return base::EndsWith(resource_path, suffix,
                                               base::CompareCase::SENSITIVE);
                       }) == disallowed_path_suffixes_.end()
-             ? Allow
-             : Disallow;
+             ? blink::WebDocumentSubresourceFilterLoadPolicy::Allow
+             : blink::WebDocumentSubresourceFilterLoadPolicy::Disallow;
 }
 
 void MockWebDocumentSubresourceFilter::reportDisallowedLoad() {}