* Added a basic tool tip API, and implementation.

* The BView API can probably be regarded as good enough; the implementation
  might need to be improved over time (also, some things as archivability
  aren't fully implemented yet). The ToolTip.h header should get public once
  finalized.
* Added new B_MOUSE_IDLE message that is sent to a BView after a certain
  time has passed (BToolTipManager::ShowDelay()).
* Added small test app (ToolTipTest) that shows what is already working.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32078 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/os/interface/Window.h

@@ -347,7 +347,7 @@ private:
 			BView*			fTopView;
 			BView*			fFocus;
 			BView*			fLastMouseMovedView;
-			uint32			_unused1;
+			BMessageRunner*	fIdleMouseRunner;
 			BMenuBar*		fKeyMenuBar;
 			BButton*		fDefaultButton;
 			BList			fShortcuts;