Getting rid of GetDefaultProfile & fixing multi user issues with accessibility

As discussed: I removed the occurances, switched the accessibility functionality with a user change and made sure that the accessibility menu is presented when at least one user has one accessibility feature turned on.

Not done:
- ChromeVox - this will most likely only partially work in multi user scenarios. It makes no sense to get this 80% working if we are in the midst of overhauling the use of ChromeVox. This needs to be re-visited once the changes are done.
- BrailleDisplayAPI - Since this is coupled with ChromeVox I guess that this falls into the same problem.
- MagnifierManager - A refactor should be done which merges this into the AccessibilityManager, but that would go beyond what we currently have to do. Besides I have found a comment which indicates that this might even be underway.


BUG=322682
TEST=unit tests (and multi profile by visual tests)

Review URL: https://codereview.chromium.org/102483006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@241010 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 14 insertions, 0 deletions

diff --git a/ash/session_state_observer.h b/ash/session_state_observer.h
index 1de31cd..de1b533 100644
--- a/ash/session_state_observer.h
+++ b/ash/session_state_observer.h
@@ -8,6 +8,7 @@
 #include <string>
 
 #include "ash/ash_export.h"
+#include "base/basictypes.h"
 
 namespace ash {
 
@@ -23,6 +24,19 @@ class ASH_EXPORT SessionStateObserver {
   virtual ~SessionStateObserver() {}
 };
 
+// A class to attach / detach an object as a session state observer with a
+// scoped pointer.
+class ASH_EXPORT ScopedSessionStateObserver {
+ public:
+  explicit ScopedSessionStateObserver(ash::SessionStateObserver* observer);
+  virtual ~ScopedSessionStateObserver();
+
+ private:
+  ash::SessionStateObserver* observer_;
+
+  DISALLOW_COPY_AND_ASSIGN(ScopedSessionStateObserver);
+};
+
 }  // namespace ash
 
 #endif  // ASH_SESSION_STATE_OBSERVER_H_