Panel auto-resize for GTK.

chrome/browser/ui/gtk/browser_window_gtk.cc

Index: chrome/browser/ui/gtk/browser_window_gtk.cc
diff --git a/chrome/browser/ui/gtk/browser_window_gtk.cc b/chrome/browser/ui/gtk/browser_window_gtk.cc
index 33b64b16d944a7fdd7c67d2491f69b203e1e220a..7ab1b0bc8728bebd9e0570b089aae075b2b54465 100644
--- a/chrome/browser/ui/gtk/browser_window_gtk.cc
+++ b/chrome/browser/ui/gtk/browser_window_gtk.cc
@@ -1898,6 +1898,13 @@ void BrowserWindowGtk::UpdateCustomFrame() {
   UpdateWindowShape(bounds_.width(), bounds_.height());
 }
 
+gfx::Size BrowserWindowGtk::GetNonClientFrameSize() const {
+  return gfx::Size(window_container_->allocation.width -
+                   render_area_floating_container_->allocation.width,
+                   window_container_->allocation.height -
+                   render_area_floating_container_->allocation.height);
+}
+
 void BrowserWindowGtk::SaveWindowPosition() {
   // Browser::SaveWindowPlacement is used for session restore.
   ui::WindowShowState show_state = ui::SHOW_STATE_NORMAL;