Some C++11 cleanup of history types.

components/history/core/browser/history_types.h

Index: components/history/core/browser/history_types.h
diff --git a/components/history/core/browser/history_types.h b/components/history/core/browser/history_types.h
index e560ed7c020ef6ba98317ac7d7a3bbe50b42202a..9189b068c5a15a32913cde65ed493b4261b6a0ce 100644
--- a/components/history/core/browser/history_types.h
+++ b/components/history/core/browser/history_types.h
@@ -78,23 +78,23 @@ class VisitRow {
   ~VisitRow();
 
   // ID of this row (visit ID, used a a referrer for other visits).
-  VisitID visit_id;
+  VisitID visit_id = 0;
 
   // Row ID into the URL table of the URL that this page is.
-  URLID url_id;
+  URLID url_id = 0;
 
   base::Time visit_time;
 
   // Indicates another visit that was the referring page for this one.
   // 0 indicates no referrer.
-  VisitID referring_visit;
+  VisitID referring_visit = 0;
 
   // A combination of bits from PageTransition.
-  ui::PageTransition transition;
+  ui::PageTransition transition = ui::PAGE_TRANSITION_LINK;
 
   // The segment id (see visitsegment_database.*).
   // If 0, the segment id is null in the table.
-  SegmentID segment_id;
+  SegmentID segment_id = 0;
 
   // Record how much time a user has this visit starting from the user
   // opened this visit to the user closed or ended this visit.
@@ -103,7 +103,7 @@ class VisitRow {
   base::TimeDelta visit_duration;
 
   // Compares two visits based on dates, for sorting.
-  bool operator<(const VisitRow& other) {
+  bool operator<(const VisitRow& other) const {
     return visit_time < other.visit_time;
   }
 
@@ -123,7 +123,7 @@ typedef std::pair<base::Time, ui::PageTransition> VisitInfo;
 // views are only interested in the time, and not the other information
 // associated with a VisitRow.
 struct PageVisit {
-  URLID page_id;
+  URLID page_id = 0;
   base::Time visit_time;
 };
 
@@ -205,7 +205,7 @@ class QueryResults {
   // time an entry with that URL appears. Normally, each URL will have one or
   // very few indices after it, so we optimize this to use statically allocated
   // memory when possible.
-  typedef std::map<GURL, base::StackVector<size_t, 4> > URLToResultIndices;
+  typedef std::map<GURL, base::StackVector<size_t, 4>> URLToResultIndices;
 
   // Inserts an entry into the |url_to_results_| map saying that the given URL
   // is at the given index in the results_.
@@ -251,8 +251,8 @@ struct QueryOptions {
 
   // The maximum number of results to return. The results will be sorted with
   // the most recent first, so older results may not be returned if there is not
-  // enough room. When 0, this will return everything (the default).
-  int max_count;
+  // enough room. When 0, this will return everything.
+  int max_count = 0;
 
   enum DuplicateHandling {
     // Omit visits for which there is a more recent visit to the same URL.
@@ -269,11 +269,12 @@ struct QueryOptions {
   };
 
   // Allows the caller to specify how duplicate URLs in the result set should
-  // be handled. The default is REMOVE_DUPLICATES.
-  DuplicateHandling duplicate_policy;
+  // be handled.
+  DuplicateHandling duplicate_policy = REMOVE_ALL_DUPLICATES;
 
   // Allows the caller to specify the matching algorithm for text queries.
-  query_parser::MatchingAlgorithm matching_algorithm;
+  query_parser::MatchingAlgorithm matching_algorithm =
+      query_parser::MatchingAlgorithm::DEFAULT;
 
   // Helpers to get the effective parameters values, since a value of 0 means
   // "unspecified".
@@ -291,7 +292,7 @@ struct QueryURLResult {
 
   // Indicates whether the call to HistoryBackend::QueryURL was successfull
   // or not. If false, then both |row| and |visits| fields are undefined.
-  bool success;
+  bool success = false;
   URLRow row;
   VisitVector visits;
 };
@@ -304,8 +305,8 @@ struct VisibleVisitCountToHostResult {
   // Indicates whether the call to HistoryBackend::GetVisibleVisitCountToHost
   // was successful or not. If false, then both |count| and |first_visit| are
   // undefined.
-  bool success;
-  int count;
+  bool success = false;
+  int count = 0;
   base::Time first_visit;
 };
 
@@ -314,11 +315,11 @@ struct VisibleVisitCountToHostResult {
 // Holds the per-URL information of the most visited query.
 struct MostVisitedURL {
   MostVisitedURL();
-  MostVisitedURL(const GURL& url, const base::string16& title);
   MostVisitedURL(const GURL& url,
                  const base::string16& title,
-                 const base::Time& last_forced_time);
+                 base::Time last_forced_time = base::Time());
   MostVisitedURL(const MostVisitedURL& other);
+  MostVisitedURL(MostVisitedURL&& other) noexcept;
   ~MostVisitedURL();
 
   GURL url;
@@ -331,6 +332,8 @@ struct MostVisitedURL {
 
   RedirectList redirects;
 
+  MostVisitedURL& operator=(const MostVisitedURL&);
+
   bool operator==(const MostVisitedURL& other) const {
     return url == other.url;
   }
@@ -343,22 +346,23 @@ struct FilteredURL {
   struct ExtendedInfo {
     ExtendedInfo();
     // The absolute number of visits.
-    unsigned int total_visits;
+    unsigned int total_visits = 0;
     // The number of visits, as seen by the Most Visited NTP pane.
-    unsigned int visits;
+    unsigned int visits = 0;
     // The total number of seconds that the page was open.
-    int64_t duration_opened;
+    int64_t duration_opened = 0;
     // The time when the page was last visited.
     base::Time last_visit_time;
   };
 
   FilteredURL();
   explicit FilteredURL(const PageUsageData& data);
+  FilteredURL(FilteredURL&& other) noexcept;
   ~FilteredURL();
 
   GURL url;
   base::string16 title;
-  double score;
+  double score = 0.0;
   ExtendedInfo extended_info;
 };
 
@@ -437,7 +441,7 @@ struct TopSitesDelta {
   MostVisitedURLWithRankList moved;
 };
 
-typedef std::map<GURL, scoped_refptr<base::RefCountedBytes> > URLToThumbnailMap;
+typedef std::map<GURL, scoped_refptr<base::RefCountedBytes>> URLToThumbnailMap;
 
 // Used when migrating most visited thumbnails out of history and into topsites.
 struct ThumbnailMigration {
@@ -479,8 +483,8 @@ typedef std::map<GURL, std::pair<int, base::Time>> OriginCountAndLastVisitMap;
 struct HistoryCountResult {
   // Indicates whether the call to HistoryBackend::GetHistoryCount was
   // successful or not. If false, then |count| is undefined.
-  bool success;
-  int count;
+  bool success = false;
+  int count = 0;
 };
 
 // Favicons -------------------------------------------------------------------
@@ -488,22 +492,26 @@ struct HistoryCountResult {
 // Used for the mapping between the page and icon.
 struct IconMapping {
   IconMapping();
+  IconMapping(const IconMapping&);
+  IconMapping(IconMapping&&) noexcept;
   ~IconMapping();
 
+  IconMapping& operator=(const IconMapping&);
+
   // The unique id of the mapping.
-  IconMappingID mapping_id;
+  IconMappingID mapping_id = 0;
 
   // The url of a web page.
   GURL page_url;
 
   // The unique id of the icon.
-  favicon_base::FaviconID icon_id;
+  favicon_base::FaviconID icon_id = 0;
 
   // The url of the icon.
   GURL icon_url;
 
   // The type of icon.
-  favicon_base::IconType icon_type;
+  favicon_base::IconType icon_type = favicon_base::INVALID_ICON;
 };
 
 // Defines a favicon bitmap and its associated pixel size.
@@ -512,7 +520,7 @@ struct FaviconBitmapIDSize {
   ~FaviconBitmapIDSize();
 
   // The unique id of the favicon bitmap.
-  FaviconBitmapID bitmap_id;
+  FaviconBitmapID bitmap_id = 0;
 
   // The pixel dimensions of the associated bitmap.
   gfx::Size pixel_size;
@@ -525,10 +533,10 @@ struct FaviconBitmap {
   ~FaviconBitmap();
 
   // The unique id of the bitmap.
-  FaviconBitmapID bitmap_id;
+  FaviconBitmapID bitmap_id = 0;
 
   // The id of the favicon to which the bitmap belongs to.
-  favicon_base::FaviconID icon_id;
+  favicon_base::FaviconID icon_id = 0;
 
   // Time at which |bitmap_data| was last updated.
   base::Time last_updated;