Retire WinJumplist.DeleteDirectoryContentDuration UMA metric

This metric is no longer needed.

Bug: 738126
Change-Id: If8baa53178238335d75ccefd8d6ae9065b2d00ad
Reviewed-on: https://chromium-review.googlesource.com/563757Reviewed-by: Ilya Sherman <isherman@chromium.org>
Reviewed-by: Patrick Monette <pmonette@chromium.org>
Commit-Queue: Xi Cheng <chengx@chromium.org>
Cr-Commit-Position: refs/heads/master@{#485355}

chrome/browser/win/jumplist.cc

@@ -841,7 +841,7 @@ int JumpList::UpdateIconFiles(const base::FilePath& icon_dir,
   //    closed" category updates for the 1st time after Chrome is launched.
   // 2) The number of icons in |icon_dir| has exceeded the limit.
   if (icon_cur->empty() || FilesExceedLimitInDir(icon_dir, max_items * 2)) {
-    DeleteDirectoryContentAndLogRuntime(icon_dir, kFileDeleteLimit);
+    DeleteDirectoryContent(icon_dir, kFileDeleteLimit);
     icon_cur->clear();
     icon_next->clear();
     // Create new icons only when the directory exists and is empty.

chrome/browser/win/jumplist_file_util.cc

@@ -83,13 +83,6 @@ void DeleteDirectory(const base::FilePath& path, int max_file_deleted) {
   ::RemoveDirectory(path.value().c_str());
 }
 
-void DeleteDirectoryContentAndLogRuntime(const base::FilePath& path,
-                                         int max_file_deleted) {
-  SCOPED_UMA_HISTOGRAM_TIMER("WinJumplist.DeleteDirectoryContentDuration");
-
-  DeleteDirectoryContent(path, kFileDeleteLimit);
-}
-
 bool FilesExceedLimitInDir(const base::FilePath& path, int max_files) {
   int count = 0;
   base::FileEnumerator file_iter(path, false, base::FileEnumerator::FILES);

chrome/browser/win/jumplist_file_util.h

@@ -34,12 +34,6 @@ void DeleteDirectoryContent(const base::FilePath& path, int max_file_deleted);
 // |path|. If |path| is empty after the call, it is removed.
 void DeleteDirectory(const base::FilePath& path, int max_file_deleted);
 
-// Deletes the content in the folder at |path| and records the runtime to UMA.
-// TODO(chengx): Remove this method and use DeleteDirectoryContent after fixing
-// http://crbug.com/40407.
-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);

tools/metrics/histograms/histograms.xml

@@ -87850,6 +87850,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="WinJumplist.DeleteDirectoryContentDuration" units="ms">
+  <obsolete>
+    Obsolete 07/06/2016 as we are no long recording this metric.
+  </obsolete>
   <owner>chengx@chromium.org</owner>
   <summary>Time spent in DeleteDirectoryContentAndLogRuntime().</summary>
 </histogram>