Factor DocumentSubresourceFilter out of SubresourceFilterAgent.

components/subresource_filter/content/renderer/subresource_filter_agent.h

Index: components/subresource_filter/content/renderer/subresource_filter_agent.h
diff --git a/components/subresource_filter/content/renderer/subresource_filter_agent.h b/components/subresource_filter/content/renderer/subresource_filter_agent.h
index a93c77acce3b5bc827b3dd16a26a0c6ba4bc4c45..b89cd88cab0bce8208d07e56f7854d94c74d3693 100644
--- a/components/subresource_filter/content/renderer/subresource_filter_agent.h
+++ b/components/subresource_filter/content/renderer/subresource_filter_agent.h
@@ -5,13 +5,23 @@
 #ifndef COMPONENTS_SUBRESOURCE_FILTER_CONTENT_RENDERER_SUBRESOURCE_FILTER_AGENT_H_
 #define COMPONENTS_SUBRESOURCE_FILTER_CONTENT_RENDERER_SUBRESOURCE_FILTER_AGENT_H_
 
+#include <memory>
+#include <vector>
+
 #include "base/macros.h"
 #include "components/subresource_filter/core/common/activation_state.h"
 #include "content/public/renderer/render_frame_observer.h"
 
+class GURL;
+
+namespace blink {
+class WebDocumentSubresourceFilter;
+}  // namespace blink
+
 namespace subresource_filter {
 
 class RulesetDealer;
+class DocumentSubresourceFilter;
 
 // The renderer-side agent of the ContentSubresourceFilterDriver. There is one
 // instance per RenderFrame, responsible for setting up the subresource filter
@@ -19,22 +29,35 @@ class RulesetDealer;
 // so by the driver.
 class SubresourceFilterAgent : public content::RenderFrameObserver {
  public:
+  // The |ruleset_dealer| must not be null and must outlive this instance. The
+  // |render_frame| may be null in unittests.
   explicit SubresourceFilterAgent(content::RenderFrame* render_frame,
                                   RulesetDealer* ruleset_dealer);
   ~SubresourceFilterAgent() override;
 
+ protected:
+  // Returns the URLs of documents loaded into nested frames starting with the
+  // current frame and ending with the main frame. The returned array is
+  // guaranteed to have at least one element. Virtual so that it can be mocked
+  // out in tests.
+  virtual std::vector<GURL> GetAncestorDocumentURLs();
+
+  // Injects the provided subresource |filter| into the DocumentLoader
+  // orchestrating the most recently committed load. Virtual so that it can be
+  // mocked out in tests.
+  virtual void SetSubresourceFilterForCommittedLoad(
+      std::unique_ptr<blink::WebDocumentSubresourceFilter> filter);
+
  private:
+  void ActivateForProvisionalLoad(ActivationState activation_state);
+
   // content::RenderFrameObserver:
   void OnDestruct() override;
   void DidStartProvisionalLoad() override;
   void DidCommitProvisionalLoad(bool is_new_navigation,
                                 bool is_same_page_navigation) override;
-
-  // content::RenderFrameObserver:
   bool OnMessageReceived(const IPC::Message& message) override;
 
-  void OnActivateForProvisionalLoad(ActivationState activation_state);
-
   // Owned by the ChromeContentRendererClient and outlives us.
   RulesetDealer* ruleset_dealer_;