Move IN_OVERFLOW from Panel::ExpansionState to new enum.

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 25ca6e03d0f6a2f888d86b3aca01a03ff8b0d9ba..3143fdeef0d894e6d31781636dcb688bbee52886 100644
--- a/chrome/browser/ui/panels/panel_manager.cc
+++ b/chrome/browser/ui/panels/panel_manager.cc
@@ -178,13 +178,20 @@ void PanelManager::EndDragging(bool cancelled) {
   panel_strip_->EndDragging(cancelled);
 }
 
-void PanelManager::OnPanelExpansionStateChanged(Panel* panel) {
-  panel_strip_->OnPanelExpansionStateChanged(panel);
-  panel_overflow_strip_->OnPanelExpansionStateChanged(panel);
+void PanelManager::OnPanelStripOwnerChanged(Panel* panel,
+                                            Panel::StripOwner old_owner) {
+  panel_strip_->OnPanelStripOwnerChanged(panel, old_owner);
+  panel_overflow_strip_->OnPanelStripOwnerChanged(panel, old_owner);
+}
+
+void PanelManager::OnPanelExpansionStateChanged(
+    Panel* panel, Panel::ExpansionState old_state) {
+  if (panel->strip_owner() == Panel::DOCKED)
+    panel_strip_->OnPanelExpansionStateChanged(panel, old_state);
 }
 
 void PanelManager::OnPanelAttentionStateChanged(Panel* panel) {
-  if (panel->expansion_state() == Panel::IN_OVERFLOW)
+  if (panel->strip_owner() == Panel::IN_OVERFLOW)
     panel_overflow_strip_->OnPanelAttentionStateChanged(panel);
 }