Change behaviour of the Alt-] and Alt-[ keys so that it cycles through SnapLeft/SnapRight to DockLe…

ash/wm/dock/docked_window_layout_manager.cc

Index: ash/wm/dock/docked_window_layout_manager.cc
diff --git a/ash/wm/dock/docked_window_layout_manager.cc b/ash/wm/dock/docked_window_layout_manager.cc
index 9eb4a12a986353d1fcce26060c6eee2e7981059d..f1879cc658c24de81b2ffc296fbbae621442760b 100644
--- a/ash/wm/dock/docked_window_layout_manager.cc
+++ b/ash/wm/dock/docked_window_layout_manager.cc
@@ -416,6 +416,7 @@ DockedWindowLayoutManager::DockedWindowLayoutManager(
                      WORKSPACE_WINDOW_STATE_FULL_SCREEN),
       docked_width_(0),
       alignment_(DOCKED_ALIGNMENT_NONE),
+      preferred_alignment_(DOCKED_ALIGNMENT_NONE),
       last_active_window_(NULL),
       last_action_time_(base::Time::Now()),
       background_widget_(new DockedBackgroundWidget(dock_container_)) {
@@ -637,7 +638,7 @@ bool DockedWindowLayoutManager::CanDockWindow(
 
 bool DockedWindowLayoutManager::IsDockedAlignmentValid(
     DockedAlignment alignment) const {
-  ShelfAlignment shelf_alignment = shelf_ ? shelf->alignment() :
+  ShelfAlignment shelf_alignment = shelf_ ? shelf_->alignment() :
       SHELF_ALIGNMENT_BOTTOM;
   if ((alignment == DOCKED_ALIGNMENT_LEFT &&
        shelf_alignment == SHELF_ALIGNMENT_LEFT) ||
@@ -692,8 +693,10 @@ void DockedWindowLayoutManager::OnWindowAddedToLayout(aura::Window* child) {
   // A window can be added without proper bounds when window is moved to another
   // display via API or due to display configuration change, so the alignment
   // is set based on which edge is closer in the new display.
-  if (alignment_ == DOCKED_ALIGNMENT_NONE)
-    alignment_ = GetEdgeNearestWindow(child);
+  if (alignment_ == DOCKED_ALIGNMENT_NONE) {
+    alignment_ = preferred_alignment_ != DOCKED_ALIGNMENT_NONE ?
+        preferred_alignment_ : GetEdgeNearestWindow(child);
+  }
   MaybeMinimizeChildrenExcept(child);
   child->AddObserver(this);
   wm::GetWindowState(child)->AddObserver(this);
@@ -854,6 +857,8 @@ void DockedWindowLayoutManager::OnPreWindowStateTypeChange(
     MinimizeDockedWindow(window_state);
   } else if (old_type == wm::WINDOW_STATE_TYPE_DOCKED_MINIMIZED) {
     RestoreDockedWindow(window_state);
+  } else if (old_type == wm::WINDOW_STATE_TYPE_MINIMIZED) {
+    NOTREACHED() << "Minimized window in docked layout manager";
   }
 }