Made launcher hidden when kicking off chrome in app mode.

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

Index: chrome/browser/ui/ash/launcher/chrome_launcher_controller_per_browser.cc
diff --git a/chrome/browser/ui/ash/launcher/chrome_launcher_controller_per_browser.cc b/chrome/browser/ui/ash/launcher/chrome_launcher_controller_per_browser.cc
index 4001dd6fafd2d09f3646256d14c81b4a6648b7e2..4fef8a68de1a6afff7347018ea169f80b5e4652e 100644
--- a/chrome/browser/ui/ash/launcher/chrome_launcher_controller_per_browser.cc
+++ b/chrome/browser/ui/ash/launcher/chrome_launcher_controller_per_browser.cc
@@ -38,9 +38,11 @@
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/browser/web_applications/web_app.h"
 #include "chrome/common/chrome_notification_types.h"
+#include "chrome/common/chrome_switches.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/extensions/extension_resource.h"
 #include "chrome/common/pref_names.h"
+#include "chrome/common/switch_utils.h"
 #include "chrome/common/url_constants.h"
 #include "content/public/browser/navigation_entry.h"
 #include "content/public/browser/notification_service.h"
@@ -658,6 +660,10 @@ bool ChromeLauncherControllerPerBrowser::CanPin() const {
 ash::ShelfAutoHideBehavior
     ChromeLauncherControllerPerBrowser::GetShelfAutoHideBehavior(
         aura::RootWindow* root_window) const {
+  // Don't show the shelf in the app mode.
+  if (switches::IsRunningInAppMode())
+    return ash::SHELF_AUTO_HIDE_ALWAYS_HIDDEN;
+
   // See comment in |kShelfAlignment| as to why we consider two prefs.
   const std::string behavior_value(
       GetPrefForRootWindow(profile_->GetPrefs(),
@@ -1130,6 +1136,11 @@ void ChromeLauncherControllerPerBrowser::SetShelfAutoHideBehaviorPrefs(
     case ash::SHELF_AUTO_HIDE_BEHAVIOR_NEVER:
       value = ash::kShelfAutoHideBehaviorNever;
       break;
+    case ash::SHELF_AUTO_HIDE_ALWAYS_HIDDEN:
+      // This one should not be a valid preference option for now. We only want
+      // to completely hide it when we run app mode.
+      NOTREACHED();
+      return;
   }
 
   UpdatePerDisplayPref(