Add ClearHistory() to ContentSuggestionsService and its providers

components/ntp_snippets/content_suggestions_service.h

Index: components/ntp_snippets/content_suggestions_service.h
diff --git a/components/ntp_snippets/content_suggestions_service.h b/components/ntp_snippets/content_suggestions_service.h
index 4f36237e62bdf74c233655eb6a26fdb9d6baf6a8..22e768673b40ade51f990199cc5992517b8349b6 100644
--- a/components/ntp_snippets/content_suggestions_service.h
+++ b/components/ntp_snippets/content_suggestions_service.h
@@ -13,6 +13,7 @@
 #include "base/callback_forward.h"
 #include "base/observer_list.h"
 #include "base/optional.h"
+#include "base/time/time.h"
 #include "components/keyed_service/core/keyed_service.h"
 #include "components/ntp_snippets/category_factory.h"
 #include "components/ntp_snippets/category_status.h"
@@ -120,6 +121,14 @@ class ContentSuggestionsService : public KeyedService,
   // called only once per provider.
   void RegisterProvider(std::unique_ptr<ContentSuggestionsProvider> provider);
 
+  // Removes history from all providers from a given time range. The data
+  // removed depends on a provider. Note that the data outside the time range
+  // may be deleted, for example suggestions, which are based on the time range.
+  // Providers should immediately clear any specified time range history-related
+  // data, such as (possibly dismissed) suggestions for NTPSnippetsService or in
+  // case of BookmarkSuggestionsProvider last visit dates.
+  void ClearHistory(base::Time begin, base::Time end);
+
   // Removes all suggestions from all caches or internal stores in all
   // providers. See |ClearCachedSuggestions|.
   void ClearAllCachedSuggestions();