Added --custom-launcher-page. Adds a page to the experimental launcher.

ash/shell/app_list.cc

Index: ash/shell/app_list.cc
diff --git a/ash/shell/app_list.cc b/ash/shell/app_list.cc
index df277d0e59e0c1d8b832f3d689428fa04d5eec51..e3968483ef84bb7abe4f48c5f42573f787f3e240 100644
--- a/ash/shell/app_list.cc
+++ b/ash/shell/app_list.cc
@@ -354,6 +354,10 @@ class ExampleAppListViewDelegate : public app_list::AppListViewDelegate {
     return NULL;
   }
 
+  virtual views::View* CreateCustomPageWebView(const gfx::Size& size) OVERRIDE {
+    return NULL;
+  }
+
   virtual bool IsSpeechRecognitionEnabled() OVERRIDE {
     return false;
   }