Implement automatic layout and stacking for docked windows

ash/wm/workspace/workspace_window_resizer.cc

Index: ash/wm/workspace/workspace_window_resizer.cc
diff --git a/ash/wm/workspace/workspace_window_resizer.cc b/ash/wm/workspace/workspace_window_resizer.cc
index 37daf19c9086f0ff39690ca93e0a34b2666a582c..ba1d2ef4c66b791b7323499981000ef1b61c0be2 100644
--- a/ash/wm/workspace/workspace_window_resizer.cc
+++ b/ash/wm/workspace/workspace_window_resizer.cc
@@ -110,7 +110,9 @@ const int kScreenEdgeInsetForTouchResize = 32;
 // Returns true if the window should stick to the edge.
 bool ShouldStickToEdge(int distance_from_edge, int sticky_size) {
   if (CommandLine::ForCurrentProcess()->HasSwitch(
-          switches::kAshEnableStickyEdges)) {
+          switches::kAshEnableStickyEdges) ||
+      CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kAshEnableDockedWindows)) {
     return distance_from_edge < 0 &&
            distance_from_edge > -sticky_size;
   }
@@ -351,8 +353,11 @@ void WorkspaceWindowResizer::Drag(const gfx::Point& location_in_parent,
   int sticky_size;
   if (event_flags & ui::EF_CONTROL_DOWN) {
     sticky_size = 0;
-  } else if (CommandLine::ForCurrentProcess()->HasSwitch(
-      switches::kAshEnableStickyEdges)) {
+  } else if (
+      CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kAshEnableStickyEdges) ||
+      CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kAshEnableDockedWindows)) {
     sticky_size = kStickyDistancePixels;
   } else if ((details_.bounds_change & kBoundsChange_Resizes) &&
       details_.source == aura::client::WINDOW_MOVE_SOURCE_TOUCH) {