Introduce activation scope logic.

components/subresource_filter/core/common/activation_scope.h

Index: components/subresource_filter/core/common/activation_scope.h
diff --git a/components/subresource_filter/core/common/activation_scope.h b/components/subresource_filter/core/common/activation_scope.h
new file mode 100644
index 0000000000000000000000000000000000000000..aa65d368b8a27de1969d83af3225556449d123a8
--- /dev/null
+++ b/components/subresource_filter/core/common/activation_scope.h
@@ -0,0 +1,29 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef COMPONENTS_SUBRESOURCE_FILTER_CORE_COMMON_ACTIVATION_SCOPE_H_
+#define COMPONENTS_SUBRESOURCE_FILTER_CORE_COMMON_ACTIVATION_SCOPE_H_
+
+#include <iosfwd>
+
+namespace subresource_filter {
+
+// Defines the scope of triggering the Safe Browsing Subresource Filter.
+enum class ActivationScope {
+  NO_SITES,
+  // Allows to activate Safe Browsing Subresource Filter only on web sites from
+  // the Safe Browsing blacklist.
+  ACTIVATION_LIST,
+  // Testing only. Allows to send activation signal to the RenderFrame for each
+  // load.
+  ALL_SITES,
+  LAST = ACTIVATION_LIST,
+};
+
+// For logging use only.
+std::ostream& operator<<(std::ostream& os, const ActivationScope& state);
+
+}  // namespace subresource_filter
+
+#endif  // COMPONENTS_SUBRESOURCE_FILTER_CORE_COMMON_ACTIVATION_SCOPE_H_