TEST ONLY: Duplicate FP rather than modifying in place

third_party/WebKit/public/platform/Platform.h

Index: third_party/WebKit/public/platform/Platform.h
diff --git a/third_party/WebKit/public/platform/Platform.h b/third_party/WebKit/public/platform/Platform.h
index 811d9f470cebb1f042c6c5baa94a0c6769b162bb..9b20ac06bada87bb651c29bc058b0d7df0cc5518 100644
--- a/third_party/WebKit/public/platform/Platform.h
+++ b/third_party/WebKit/public/platform/Platform.h
@@ -685,6 +685,10 @@ class BLINK_PLATFORM_EXPORT Platform {
 
   // Feature Policy -----------------------------------------------------
 
+  // Create a new feature policy object for a document, given its parent
+  // document's policy (may be nullptr), its container policy (may be empty),
+  // the header policy with which it was delivered (may be empty), and the
+  // document's origin.
   virtual WebFeaturePolicy* createFeaturePolicy(
       const WebFeaturePolicy* parentPolicy,
       const WebParsedFeaturePolicyHeader& containerPolicy,
@@ -692,8 +696,14 @@ class BLINK_PLATFORM_EXPORT Platform {
       const WebSecurityOrigin&) {
     return nullptr;
   }
-  virtual void resetFeaturePolicyOrigin(WebFeaturePolicy* parentPolicy,
-                                        const WebSecurityOrigin&) {}
+
+  // Create a new feature policy for a document whose origin has changed, given
+  // the previous policy object and the new origin.
+  virtual WebFeaturePolicy* duplicateFeaturePolicyWithOrigin(
+      const WebFeaturePolicy&,
+      const WebSecurityOrigin&) {
+    return nullptr;
+  }
 
  protected:
   Platform();