Rename DesktopEngagement* to DesktopSessionDuration*.

chrome/browser/metrics/desktop_session/audible_contents_tracker.h

Index: chrome/browser/metrics/desktop_session/audible_contents_tracker.h
diff --git a/chrome/browser/metrics/desktop_engagement/audible_contents_tracker.h b/chrome/browser/metrics/desktop_session/audible_contents_tracker.h
similarity index 87%
rename from chrome/browser/metrics/desktop_engagement/audible_contents_tracker.h
rename to chrome/browser/metrics/desktop_session/audible_contents_tracker.h
index cc3e515e7b6bb1b5ccb95d7ab19ce58c9d2e8aad..cff79b5c1d61b6d848d2317ea954d5fa689b86c6 100644
--- a/chrome/browser/metrics/desktop_engagement/audible_contents_tracker.h
+++ b/chrome/browser/metrics/desktop_session/audible_contents_tracker.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef CHROME_BROWSER_METRICS_DESKTOP_ENGAGEMENT_AUDIBLE_CONTENTS_TRACKER_H_
-#define CHROME_BROWSER_METRICS_DESKTOP_ENGAGEMENT_AUDIBLE_CONTENTS_TRACKER_H_
+#ifndef CHROME_BROWSER_METRICS_DESKTOP_SESSION_AUDIBLE_CONTENTS_TRACKER_H_
+#define CHROME_BROWSER_METRICS_DESKTOP_SESSION_AUDIBLE_CONTENTS_TRACKER_H_
 
 #include <set>
 
@@ -18,8 +18,8 @@ class AudibleContentsTracker : public chrome::BrowserListObserver,
                                public TabStripModelObserver {
  public:
   // Interface for an observer of the AudibleContentsTracker. The only client
-  // of this class is the DesktopEngagementService, but an observer interface
-  // has been created for ease of testing.
+  // of this class is the DesktopSessionService, but an observer interface has
+  // been created for ease of testing.
   class Observer {
    public:
     Observer() {}
@@ -73,4 +73,4 @@ class AudibleContentsTracker : public chrome::BrowserListObserver,
 
 }  // namespace metrics
 
-#endif  // CHROME_BROWSER_METRICS_DESKTOP_ENGAGEMENT_AUDIBLE_CONTENTS_TRACKER_H_
+#endif  // CHROME_BROWSER_METRICS_DESKTOP_SESSION_AUDIBLE_CONTENTS_TRACKER_H_