Attempt 2: Allows tab dragging when maximized on aura. To fix it I made it so

chrome/browser/ui/views/tabs/tab_drag_controller2.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/views/tabs/tab_drag_controller2.h"
 
 #include <math.h>
 #include <set>
 
 #include "base/callback.h"
@@ skipping 22 matching lines @@
 #include "ui/base/animation/animation_delegate.h"
 #include "ui/base/animation/slide_animation.h"
 #include "ui/base/events.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/canvas_skia.h"
 #include "ui/gfx/screen.h"
 #include "ui/views/events/event.h"
 #include "ui/views/widget/root_view.h"
 #include "ui/views/widget/widget.h"
 
+#if defined(USE_AURA)
+#include "ash/wm/property_util.h"
+#endif
+
 using content::UserMetricsAction;
 using content::WebContents;
 
 static const int kHorizontalMoveThreshold = 16;  // Pixels.
 
 // If non-null there is a drag underway.
 static TabDragController2* instance_;
 
 namespace {
 
@@ skipping 262 matching lines @@
   instance_ = this;
 }
 
 TabDragController2::~TabDragController2() {
   if (instance_ == this)
     instance_ = NULL;
 
   if (destroyed_)
     *destroyed_ = true;
 
-  if (move_loop_browser_view_)
+  if (move_loop_browser_view_) {
     move_loop_browser_view_->set_move_observer(NULL);
+    SetTrackedByWorkspace(
+        move_loop_browser_view_->GetWidget()->GetNativeView(), true);
+  }
 
   if (source_tabstrip_)
     GetModel(source_tabstrip_)->RemoveObserver(this);
 
   MessageLoopForUI::current()->RemoveObserver(this);
 }
 
 void TabDragController2::Init(
     TabStrip* source_tabstrip,
     BaseTab* source_tab,
@@ skipping 752 matching lines @@
   return tabs;
 }
 
 void TabDragController2::EndDragImpl(EndDragType type) {
   DCHECK(active_);
   active_ = false;
 
   bring_to_front_timer_.Stop();
 
   if (is_dragging_window_) {
+    if (type == NORMAL || (type == TAB_DESTROYED && drag_data_.size() > 1)) {
+      SetTrackedByWorkspace(
+          GetAttachedBrowserView()->GetWidget()->GetNativeView(), true);
+    }
+
     // End the nested drag loop.
     GetAttachedBrowserView()->GetWidget()->EndMoveLoop();
     waiting_for_run_loop_to_exit_ = true;
   }
 
   // Hide the current dock controllers.
   for (size_t i = 0; i < dock_controllers_.size(); ++i) {
     // Be sure and clear the controller first, that way if Hide ends up
     // deleting the controller it won't call us back.
     dock_controllers_[i]->clear_controller();
@@ skipping 275 matching lines @@
       int delta = (*drag_bounds)[0].x();
       for (size_t i = 0; i < drag_bounds->size(); ++i)
         (*drag_bounds)[i].Offset(-delta, 0);
       break;
     }
 
     default:
       break; // Nothing to do for DETACH_ABOVE_OR_BELOW.
   }
 
+  SetTrackedByWorkspace(browser->window()->GetNativeHandle(), false);
   browser->window()->SetBounds(new_bounds);
   return browser;
 }
+
+void TabDragController2::SetTrackedByWorkspace(gfx::NativeWindow window,
+                                               bool value) {
+#if defined(USE_AURA)
+  ash::SetTrackedByWorkspace(window, value);
+#endif
+}