Distinguish between subresource filtering and dryrun matching.

third_party/WebKit/public/platform/WebDocumentSubresourceFilter.h

Index: third_party/WebKit/public/platform/WebDocumentSubresourceFilter.h
diff --git a/third_party/WebKit/public/platform/WebDocumentSubresourceFilter.h b/third_party/WebKit/public/platform/WebDocumentSubresourceFilter.h
index 71e33d5ab77097072e3abe2b4ebe7bc6c19c6154..11b9ca7c7e04a9729843123cfc6d882536baf363 100644
--- a/third_party/WebKit/public/platform/WebDocumentSubresourceFilter.h
+++ b/third_party/WebKit/public/platform/WebDocumentSubresourceFilter.h
@@ -13,9 +13,11 @@ class WebURL;
 
 class WebDocumentSubresourceFilter {
  public:
+  enum LoadPolicy { Allow, Filter, AllowWouldFilter };

[engedy, 2017/02/06 16:56:32]

nit: I find the term `filter` somewhat ambiguous: does it mean the act of
filtering, or the query matching the filter? I'm not a native speaker, though.
What do you think about `Disallow`? 

Then the third option could be, e.g., just `WouldDisallow`. Maybe we could add
comment?

[Bryan McQuade, 2017/02/06 17:11:56]

Good suggestion, thanks! Updated to Allow/Disallow/WouldDisallow.

   virtual ~WebDocumentSubresourceFilter() {}
-  virtual bool allowLoad(const WebURL& resourceUrl,
-                         WebURLRequest::RequestContext) = 0;
+  virtual LoadPolicy getLoadPolicy(const WebURL& resourceUrl,
+                                   WebURLRequest::RequestContext) = 0;
+  virtual void reportFilteredLoad() = 0;
 };
 
 }  // namespace blink