Revert of Add OnDisplayMetricsChanged in DisplayObserver.

chrome/browser/ui/webui/options/chromeos/display_overscan_handler.cc

Index: chrome/browser/ui/webui/options/chromeos/display_overscan_handler.cc
diff --git a/chrome/browser/ui/webui/options/chromeos/display_overscan_handler.cc b/chrome/browser/ui/webui/options/chromeos/display_overscan_handler.cc
index d7d5d929f9c31fc5ff6273ae039f93b1fed067cd..c176b0b0ca89cca60a61423176d420d807344d72 100644
--- a/chrome/browser/ui/webui/options/chromeos/display_overscan_handler.cc
+++ b/chrome/browser/ui/webui/options/chromeos/display_overscan_handler.cc
@@ -81,6 +81,10 @@
                  base::Unretained(this)));
 }
 
+void DisplayOverscanHandler::OnDisplayBoundsChanged(
+    const gfx::Display& display) {
+}
+
 void DisplayOverscanHandler::OnDisplayAdded(const gfx::Display& new_display) {
   web_ui()->CallJavascriptFunction(
       "options.DisplayOverscan.onOverscanCanceled");
@@ -89,10 +93,6 @@
 void DisplayOverscanHandler::OnDisplayRemoved(const gfx::Display& old_display) {
   web_ui()->CallJavascriptFunction(
       "options.DisplayOverscan.onOverscanCanceled");
-}
-
-void DisplayOverscanHandler::OnDisplayMetricsChanged(const gfx::Display&,
-                                                     uint32_t) {
 }
 
 void DisplayOverscanHandler::HandleStart(const base::ListValue* args) {