Implement automatic layout and stacking for docked windows

ash/wm/dock/docked_window_resizer.cc

Index: ash/wm/dock/docked_window_resizer.cc
diff --git a/ash/wm/dock/docked_window_resizer.cc b/ash/wm/dock/docked_window_resizer.cc
index fc880d76a27dab0e94a0a3be2223706220a47f54..224adb641530c2923616fa990c91b887d07af25a 100644
--- a/ash/wm/dock/docked_window_resizer.cc
+++ b/ash/wm/dock/docked_window_resizer.cc
@@ -174,7 +174,7 @@ bool DockedWindowResizer::MaybeSnapToEdge(const gfx::Rect& bounds,
       (dock_alignment == internal::DOCKED_ALIGNMENT_NONE && was_docked_)) {
     const int distance = bounds.x() - dock_bounds.x();
     if (distance < kSnapToDockDistance && distance > -kStickyDistance) {
-      offset->set_x(dock_bounds.x() - bounds.x());
+      offset->set_x(-distance);
       return true;
     }
   }
@@ -182,7 +182,7 @@ bool DockedWindowResizer::MaybeSnapToEdge(const gfx::Rect& bounds,
       (dock_alignment == internal::DOCKED_ALIGNMENT_NONE && was_docked_)) {
     const int distance = dock_bounds.right() - bounds.right();
     if (distance < kSnapToDockDistance && distance > -kStickyDistance) {
-      offset->set_x(dock_bounds.right() - bounds.right());
+      offset->set_x(distance);
       return true;
     }
   }
@@ -213,6 +213,10 @@ void DockedWindowResizer::FinishDragging() {
   if (should_dock !=
       (window->parent()->id() == internal::kShellWindowId_DockedContainer)) {
     if (should_dock) {
+      // Panel resizer might have attached this to the launcher.
+      // Docked resizer takes priority and may attach it to the docked area.
+      if (window->type() == aura::client::WINDOW_TYPE_PANEL)
+        window->SetProperty(internal::kPanelAttachedKey, false);

[flackr, 2013/07/16 22:05:45]

Separate CL please.

[varkha, 2013/07/18 21:56:59]

Done.

       aura::Window* dock_container = Shell::GetContainer(
           window->GetRootWindow(),
           internal::kShellWindowId_DockedContainer);