Add window states docked; and docked minimized. Add wm window event to set docked and undocked.

ash/wm/wm_types.h

Index: ash/wm/wm_types.h
diff --git a/ash/wm/wm_types.h b/ash/wm/wm_types.h
index 2045deb9d776dc7e018cec12c5b41c4271ab31d4..7a78bcbe1c9a681af1547dbe38c58265d83e8af3 100644
--- a/ash/wm/wm_types.h
+++ b/ash/wm/wm_types.h
@@ -12,7 +12,7 @@ namespace ash {
 namespace wm {
 
 // This enum defines both common show state copied from
-// ui::WindowShowState as well as new states intoruduced in ash.
+// ui::WindowShowState as well as new states introduced in ash.
 // The separate enum is defined here because we don't want to leak
 // these type to ui/base until they're stable and we know for sure
 // that they'll persist over time.
@@ -34,6 +34,9 @@ enum WindowStateType {
   WINDOW_STATE_TYPE_LEFT_SNAPPED,
   WINDOW_STATE_TYPE_RIGHT_SNAPPED,
 
+  WINDOW_STATE_TYPE_DOCKED,
+  WINDOW_STATE_TYPE_DOCKED_MINIMIZED,
+
   // A window is in this state when it is automatically placed and
   // sized by the window manager. (it's newly opened, or pushed to the side
   // due to new window, for example).