Add OnDisplayMetricsChanged in DisplayObserver.

chrome/browser/ui/ash/launcher/browser_status_monitor.cc

Index: chrome/browser/ui/ash/launcher/browser_status_monitor.cc
diff --git a/chrome/browser/ui/ash/launcher/browser_status_monitor.cc b/chrome/browser/ui/ash/launcher/browser_status_monitor.cc
index f10792cb08257a9bcb6ab4bfa4968a64dad7231e..ab27c2c88fd26a7b3eb05fae000e47106940e1ed 100644
--- a/chrome/browser/ui/ash/launcher/browser_status_monitor.cc
+++ b/chrome/browser/ui/ash/launcher/browser_status_monitor.cc
@@ -227,11 +227,6 @@ void BrowserStatusMonitor::OnBrowserRemoved(Browser* browser) {
   UpdateBrowserItemState();
 }
 
-void BrowserStatusMonitor::OnDisplayBoundsChanged(
-    const gfx::Display& display) {
-  // Do nothing here.
-}
-
 void BrowserStatusMonitor::OnDisplayAdded(const gfx::Display& new_display) {
   // Add a new RootWindow and its ActivationClient to observed list.
   aura::Window* root_window = ash::Shell::GetInstance()->
@@ -252,6 +247,11 @@ void BrowserStatusMonitor::OnDisplayRemoved(const gfx::Display& old_display) {
   // Do nothing here.
 }
 
+void BrowserStatusMonitor::OnDisplayMetricsChanged(
+    const gfx::Display&, DisplayObserver::DisplayMetrics) {
+  // Do nothing here.
+}
+
 void BrowserStatusMonitor::ActiveTabChanged(content::WebContents* old_contents,
                                             content::WebContents* new_contents,
                                             int index,