[Thumbnails DB] Add functionality to clear unused on-demand favicons.

components/history/core/browser/history_types.cc

 // Copyright 2014 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.
 
 #include "components/history/core/browser/history_types.h"
 
 #include <limits>
 
 #include "base/logging.h"
 #include "base/stl_util.h"
@@ skipping 281 matching lines @@
 IconMapping::~IconMapping() {}
 
 IconMapping& IconMapping::operator=(const IconMapping&) = default;
 
 // FaviconBitmapIDSize ---------------------------------------------------------
 
 FaviconBitmapIDSize::FaviconBitmapIDSize() {}
 
 FaviconBitmapIDSize::~FaviconBitmapIDSize() {}
 
+// IconMappingsForExpiry ------------------------------------------------------
+
+IconMappingsForExpiry::IconMappingsForExpiry() {}
+
+IconMappingsForExpiry::IconMappingsForExpiry(
+    const IconMappingsForExpiry& other) = default;
+
+IconMappingsForExpiry::~IconMappingsForExpiry() {}
+
 // FaviconBitmap --------------------------------------------------------------
 
 FaviconBitmap::FaviconBitmap() {}
 
 FaviconBitmap::FaviconBitmap(const FaviconBitmap& other) = default;
 
 FaviconBitmap::~FaviconBitmap() {}
 
 // ExpireHistoryArgs ----------------------------------------------------------
 
 ExpireHistoryArgs::ExpireHistoryArgs() {
 }
 
 ExpireHistoryArgs::ExpireHistoryArgs(const ExpireHistoryArgs& other) = default;
 
 ExpireHistoryArgs::~ExpireHistoryArgs() {
 }
 
 void ExpireHistoryArgs::SetTimeRangeForOneDay(base::Time time) {
   begin_time = time.LocalMidnight();
 
   // Due to DST, leap seconds, etc., the next day at midnight may be more than
   // 24 hours away, so add 36 hours and round back down to midnight.
   end_time = (begin_time + base::TimeDelta::FromHours(36)).LocalMidnight();
 }
 
 }  // namespace history