Feature policy: Add basic algorithm for supporting frame policies.

third_party/WebKit/Source/platform/feature_policy/FeaturePolicy.h

Index: third_party/WebKit/Source/platform/feature_policy/FeaturePolicy.h
diff --git a/third_party/WebKit/Source/platform/feature_policy/FeaturePolicy.h b/third_party/WebKit/Source/platform/feature_policy/FeaturePolicy.h
index 47b22e6b7951c1183d00a0ce4e824b48c75495cc..f188d66b7dfc42fbd403078c3b526988a40e3d48 100644
--- a/third_party/WebKit/Source/platform/feature_policy/FeaturePolicy.h
+++ b/third_party/WebKit/Source/platform/feature_policy/FeaturePolicy.h
@@ -138,6 +138,7 @@ class PLATFORM_EXPORT FeaturePolicy final {
 
   static std::unique_ptr<FeaturePolicy> createFromParentPolicy(
       const FeaturePolicy* parent,
+      const WebParsedFeaturePolicy* framePolicy,
       RefPtr<SecurityOrigin>);
 
   // Sets the declared policy from the parsed Feature-Policy HTTP header.
@@ -164,9 +165,13 @@ class PLATFORM_EXPORT FeaturePolicy final {
 
   static std::unique_ptr<FeaturePolicy> createFromParentPolicy(
       const FeaturePolicy* parent,
+      const WebParsedFeaturePolicy* framePolicy,
       RefPtr<SecurityOrigin>,
       FeatureList& features);
 
+  void addFramePolicy(const FeaturePolicy* parent,
+                      const WebParsedFeaturePolicy* framePolicy);
+
   RefPtr<SecurityOrigin> m_origin;
 
   // Records whether or not each feature was enabled for this frame by its