Introduce activation scope logic.

components/subresource_filter/core/browser/subresource_filter_features.h

Index: components/subresource_filter/core/browser/subresource_filter_features.h
diff --git a/components/subresource_filter/core/browser/subresource_filter_features.h b/components/subresource_filter/core/browser/subresource_filter_features.h
index 612a2d9f1d6956d56b0dd45c5c63d56c826d9ac1..fba7e2267802b5d309e4b542059eb39e49a5a700 100644
--- a/components/subresource_filter/core/browser/subresource_filter_features.h
+++ b/components/subresource_filter/core/browser/subresource_filter_features.h
@@ -6,12 +6,15 @@
 #define COMPONENTS_SUBRESOURCE_FILTER_SUBRESOURCE_FILTER_FEATURES_H_
 
 #include "base/feature_list.h"
+#include "components/subresource_filter/core/common/activation_scope.h"
 #include "components/subresource_filter/core/common/activation_state.h"
 
 namespace subresource_filter {
 
 // The master toggle to enable/disable the Safe Browsing Subresource Filter.
 extern const base::Feature kSafeBrowsingSubresourceFilter;
+// The toggle which controls scope of the activation.
+extern const base::Feature kSafeBrowsingSubresourceFilterScope;
 
 // Name/values of the variation parameter controlling maximum activation state.
 extern const char kActivationStateParameterName[];
@@ -19,11 +22,22 @@ extern const char kActivationStateDryRun[];
 extern const char kActivationStateEnabled[];
 extern const char kActivationStateDisabled[];
 
+extern const char kActivationScopeParameterName[];
+extern const char kActivationScopeAllSites[];
+extern const char kActivationScopeActivationList[];
+extern const char kActivationScopeDisabled[];
+
 // Returns the maximum degree to which subresource filtering should be activated
 // on any RenderFrame. This will be ActivationState::DISABLED unless the feature
 // is enabled and variation parameters prescribe a higher activation state.
 ActivationState GetMaximumActivationState();
 
+// Returns current activation scope, so the appropriate activation signal can be
+// send to the RenderFrame. The function returns ActivationScope::DESABLED
+// unless the feature is enabled and variation parameters prescribe a higher
+// activation state.
+ActivationScope GetCurrentActivationScope();
+
 }  // namespace subresource_filter
 
 #endif  // COMPONENTS_SUBRESOURCE_FILTER_SUBRESOURCE_FILTER_FEATURES_H_