Clear session-only data when all browser windows are closed.

chrome/browser/background/background_mode_manager.h

Index: chrome/browser/background/background_mode_manager.h
diff --git a/chrome/browser/background/background_mode_manager.h b/chrome/browser/background/background_mode_manager.h
index 118d38693ae9d49c27e47a14ee628dc520a11670..0494f5a2abde2d94d568fa040e1ab993c5ea767d 100644
--- a/chrome/browser/background/background_mode_manager.h
+++ b/chrome/browser/background/background_mode_manager.h
@@ -60,6 +60,9 @@ class BackgroundModeManager
   static void LaunchBackgroundApplication(Profile* profile,
       const extensions::Extension* extension);
 
+  // Returns true if background mode is active.
+  virtual bool IsBackgroundModeActive();
+
   // For testing purposes.
   int NumberOfBackgroundModeData();
 
@@ -246,9 +249,6 @@ class BackgroundModeManager
   // (virtual to allow overriding in tests).
   virtual bool IsBackgroundModePrefEnabled() const;
 
-  // Returns true if background mode is active. Used only by tests.
-  bool IsBackgroundModeActiveForTest();
-
   // Turns off background mode if it's currently enabled.
   void DisableBackgroundMode();