Cleanup to keep panel from manipulating its panel strip assignment directly.

chrome/browser/ui/panels/panel_manager.cc

Index: chrome/browser/ui/panels/panel_manager.cc
diff --git a/chrome/browser/ui/panels/panel_manager.cc b/chrome/browser/ui/panels/panel_manager.cc
index c918b8a0d9c510fdc0e6ec7146f1df72df4e3fa5..0013a5337022788184f717582b3bea6427c7773d 100644
--- a/chrome/browser/ui/panels/panel_manager.cc
+++ b/chrome/browser/ui/panels/panel_manager.cc
@@ -117,7 +117,7 @@ Panel* PanelManager::CreatePanel(Browser* browser) {
   int width = browser->override_bounds().width();
   int height = browser->override_bounds().height();
   Panel* panel = new Panel(browser, gfx::Size(width, height));
-  panel->MoveToStrip(docked_strip_.get());
+  docked_strip_->AddPanel(panel);
 
   content::NotificationService::current()->Notify(
       chrome::NOTIFICATION_PANEL_ADDED,
@@ -147,10 +147,11 @@ void PanelManager::CheckFullScreenMode() {
 }
 
 void PanelManager::OnPanelClosed(Panel* panel) {
-  if (num_panels() == 0)
+  if (num_panels() == 1)
     full_screen_mode_timer_.Stop();
 
   drag_controller_->OnPanelClosed(panel);
+  panel->panel_strip()->RemovePanel(panel);
 
   content::NotificationService::current()->Notify(
       chrome::NOTIFICATION_PANEL_CLOSED,
@@ -192,6 +193,74 @@ void PanelManager::ResizePanel(Panel* panel, const gfx::Size& new_size) {
   docked_strip_->ResizePanelWindow(panel, new_size);
 }
 
+void PanelManager::MovePanelToStrip(Panel* panel,
+                                    PanelStrip::Type new_layout) {
+  DCHECK(panel);
+  PanelStrip* current_strip = panel->panel_strip();
+  DCHECK(current_strip);
+  DCHECK_NE(current_strip->type(), new_layout);
+  current_strip->RemovePanel(panel);
+
+  PanelStrip* target_strip = NULL;
+  switch (new_layout) {
+    case PanelStrip::DETACHED:
+      target_strip = detached_strip_.get();
+      break;
+    case PanelStrip::DOCKED:
+      EnsurePanelFitsInDock(panel);
+      target_strip = docked_strip_.get();
+      break;
+    case PanelStrip::IN_OVERFLOW:
+      target_strip = overflow_strip_.get();
+      break;
+    default:
+      NOTREACHED();
+  }
+
+  target_strip->AddPanel(panel);
+
+  content::NotificationService::current()->Notify(
+      chrome::NOTIFICATION_PANEL_CHANGED_LAYOUT_MODE,
+      content::Source<Panel>(panel),
+      content::NotificationService::NoDetails());
+}
+
+void PanelManager::EnsurePanelFitsInDock(Panel* panel) {

[jianli, 2012/03/02 02:26:09]

nit: EnsurePanelFitsInDockedStrip?

+  // Prevent layout refreshes while adjusting panels.
+  docked_strip_->enable_layout_refresh(false);
+  while (!docked_strip_->CanFitPanel(panel))
+    MovePanelToStrip(docked_strip_->last_panel(), PanelStrip::IN_OVERFLOW);

[jianli, 2012/03/02 02:26:09]

We know that we start from last docked panel and move it into overflow. When
DockedPanelStrip::RemovePanel is called, we still search the whole list to
remove it. Could we be smarter to deal with this more efficiently?

+  docked_strip_->enable_layout_refresh(true);  // Re-enable.
+}
+
+void PanelManager::MovePanelsToOverflow(Panel* last_panel_to_move) {
+  // Prevent layout refreshes while adjusting panels.
+  docked_strip_->enable_layout_refresh(false);
+
+  // Move panels to overflow in reverse to maintain their order.
+  Panel* bumped_panel;
+  while ((bumped_panel = docked_strip_->last_panel())) {
+    MovePanelToStrip(bumped_panel, PanelStrip::IN_OVERFLOW);

[jianli, 2012/03/02 02:26:09]

ditto.

+    if (bumped_panel == last_panel_to_move)
+      break;
+  }
+  DCHECK(!docked_strip_->panels().empty());
+
+  docked_strip_->enable_layout_refresh(true);  // Re-enable.
+}
+
+void PanelManager::MovePanelsOutOfOverflowIfCanFit() {
+  // Prevent layout refreshes while adjusting panels.
+  docked_strip_->enable_layout_refresh(false);
+
+  Panel* overflow_panel;
+  while ((overflow_panel = overflow_strip_->first_panel()) &&
+         docked_strip_->CanFitPanel(overflow_panel))
+    MovePanelToStrip(overflow_panel, PanelStrip::DOCKED);
+
+  docked_strip_->enable_layout_refresh(true);  // Re-enable.
+}
+
 bool PanelManager::ShouldBringUpTitlebars(int mouse_x, int mouse_y) const {
   return docked_strip_->ShouldBringUpTitlebars(mouse_x, mouse_y);
 }