Remove --ash-disable-overview-mode

ash/ash_switches.cc

Index: ash/ash_switches.cc
diff --git a/ash/ash_switches.cc b/ash/ash_switches.cc
index da289bb141c5c137317e4f46348d59892f595f66..4375264a00bb17c20e2d4c5ef402cf0ccecf4405 100644
--- a/ash/ash_switches.cc
+++ b/ash/ash_switches.cc
@@ -53,9 +53,6 @@ const char kAshDisableAudioDeviceMenu[] =
 // Disable ability to dock windows at the desktop edge.
 const char kAshDisableDockedWindows[] = "ash-disable-docked-windows";
 
-// Disables overview mode for window switching.
-const char kAshDisableOverviewMode[] = "ash-disable-overview-mode";
-
 // Use alternate visual style for the caption buttons (minimize, maximize,
 // restore, close). The alternate style:
 // - Adds a dedicated button for minimize.
@@ -148,10 +145,6 @@ bool UseImmersiveFullscreenForAllWindows() {
       kAshEnableImmersiveFullscreenForBrowserOnly);
 }
 
-bool UseOverviewMode() {
-  return !CommandLine::ForCurrentProcess()->HasSwitch(kAshDisableOverviewMode);
-}
-
 bool UseDockedWindows() {
   return !CommandLine::ForCurrentProcess()->HasSwitch(kAshDisableDockedWindows);
 }