chromeos: Stop calling ProfileManager::GetDefaultProfile() from extension event dispatch functions

chrome/browser/chromeos/power/brightness_observer.h

Index: chrome/browser/chromeos/power/brightness_observer.h
diff --git a/chrome/browser/chromeos/power/brightness_observer.h b/chrome/browser/chromeos/power/brightness_observer.h
index 878122c27d41f323097972b743f438df90d9e0a7..084d31960ce0ec3eca67fa9e2b54dd4e8f7a909f 100644
--- a/chrome/browser/chromeos/power/brightness_observer.h
+++ b/chrome/browser/chromeos/power/brightness_observer.h
@@ -9,6 +9,8 @@
 #include "base/compiler_specific.h"
 #include "chromeos/dbus/power_manager_client.h"
 
+class Profile;
+
 namespace chromeos {
 
 // This observer listens for changes to the screen brightness and notifies
@@ -16,13 +18,15 @@ namespace chromeos {
 class BrightnessObserver : public PowerManagerClient::Observer {
  public:
   // This class registers/unregisters itself as an observer in ctor/dtor.
-  BrightnessObserver();
+  explicit BrightnessObserver(Profile* profile);
   virtual ~BrightnessObserver();
 
  private:
   // PowerManagerClient::Observer implementation.
   virtual void BrightnessChanged(int level, bool user_initiated) OVERRIDE;
 
+  Profile* profile_;
+
   DISALLOW_COPY_AND_ASSIGN(BrightnessObserver);
 };