Move GetWebstoreLaunchURL and GetWebstoreItemDetailURLPrefix to extensions/common/extension_urls.h.

extensions/common/switches.cc

Index: extensions/common/switches.cc
diff --git a/extensions/common/switches.cc b/extensions/common/switches.cc
index 674bb03e4e4edbd7bfc1203a96384c549c3e2f18..0c9a7ed74d4cce5e6e24aad6e7e8c552bb2a696a 100644
--- a/extensions/common/switches.cc
+++ b/extensions/common/switches.cc
@@ -18,6 +18,9 @@ const char kAllowLegacyExtensionManifests[] =
 // automation testing of the gallery.
 const char kAllowScriptingGallery[]         = "allow-scripting-gallery";
 
+// The URL to use for the gallery link in the app launcher.
+const char kAppsGalleryURL[]                = "apps-gallery-url";
+
 // Enables extension APIs that are in development.
 const char kEnableExperimentalExtensionApis[] =
     "enable-experimental-extension-apis";