Add key modifier on minimize/restore button click to minimize/restore all Panels for Mac.

chrome/browser/ui/panels/detached_panel_strip.cc

Index: chrome/browser/ui/panels/detached_panel_strip.cc
diff --git a/chrome/browser/ui/panels/detached_panel_strip.cc b/chrome/browser/ui/panels/detached_panel_strip.cc
index 763abeee8bb51b120403bc87cc40201eb51524f8..5b5ea18a334c03ff519c45fc69dfd2a7d84868bf 100644
--- a/chrome/browser/ui/panels/detached_panel_strip.cc
+++ b/chrome/browser/ui/panels/detached_panel_strip.cc
@@ -110,6 +110,16 @@ void DetachedPanelStrip::RestorePanel(Panel* panel) {
   // regardless of which strip the panel is in. So we just quietly return.
 }
 
+void DetachedPanelStrip::MinimizeAll() {
+  // Detached panels do not minimize.
+  NOTREACHED();
+}
+
+void DetachedPanelStrip::RestoreAll() {
+  // Detached panels do not minimize.
+  NOTREACHED();
+}
+
 bool DetachedPanelStrip::CanMinimizePanel(const Panel* panel) const {
   DCHECK_EQ(this, panel->panel_strip());
   // Detached panels do not minimize.