Cache JumpList icons to avoid unnecessary creation and deletion

chrome/browser/win/jumplist_file_util.h

Index: chrome/browser/win/jumplist_file_util.h
diff --git a/chrome/browser/win/jumplist_file_util.h b/chrome/browser/win/jumplist_file_util.h
index 6d53ec2595271bf78e2a04ba2735859baf45e628..7b74dcd0d33aa4e5e9473a6bac2db6b1191ada57 100644
--- a/chrome/browser/win/jumplist_file_util.h
+++ b/chrome/browser/win/jumplist_file_util.h
@@ -5,6 +5,8 @@
 #ifndef CHROME_BROWSER_WIN_JUMPLIST_FILE_UTIL_H_
 #define CHROME_BROWSER_WIN_JUMPLIST_FILE_UTIL_H_
 
+#include <set>
+
 #include "base/files/file_path.h"
 
 // Maximum number of icon files allowed to delete per jumplist update.
@@ -39,4 +41,12 @@ void DeleteDirectory(const base::FilePath& path, int max_file_deleted);
 void DeleteDirectoryContentAndLogRuntime(const base::FilePath& path,
                                          int max_file_deleted);
 
+// Returns true if the directory at |path| has more than |max_files| files.
+// Sub-directories are not taken into account here.
+bool FilesExceedLimitInDir(const base::FilePath& path, int max_files);
+
+// Deletes all files in the directory at |path| but not in set |iconpath_set|.
+void DeleteNonCachedFiles(const base::FilePath& path,
+                          const std::set<base::FilePath>& iconpath_set);

[grt (UTC plus 2), 2017/05/11 20:29:13]

nit: iconpath_set -> cached_files since these are the files not deleted (the
"cached files")

[chengx, 2017/05/12 01:04:24]

Done.

+
 #endif  // CHROME_BROWSER_WIN_JUMPLIST_FILE_UTIL_H_