Remove enable_media_router.

chrome/common/extensions/extension_constants.cc

Index: chrome/common/extensions/extension_constants.cc
diff --git a/chrome/common/extensions/extension_constants.cc b/chrome/common/extensions/extension_constants.cc
index 5923f7efc6c671cde7ff6741fa145c8cc7eeda49..4c3aee0dfcb30a1278fa20b0827d5b432d16849b 100644
--- a/chrome/common/extensions/extension_constants.cc
+++ b/chrome/common/extensions/extension_constants.cc
@@ -53,9 +53,7 @@ const char kHotwordNewExtensionId[] = "nbpagnldghgfoolbancepceaanlmhfmd";
 const char kHotwordSharedModuleId[] = "lccekmodgklaepjeofjdjpbminllajkg";
 const char kYoutubeAppId[] = "blpcfgokakmgnkcojhhkbfbldkacnbeo";
 const char kInAppPaymentsSupportAppId[] = "nmmhkkegccagdldgiimedpiccmgmieda";
-#if defined(ENABLE_MEDIA_ROUTER)
 const char kMediaRouterStableExtensionId[] = "pkedcjkdefgpdelpbcmbmeomcjbeemfm";
-#endif  // defined(ENABLE_MEDIA_ROUTER)
 
 #if defined(OS_CHROMEOS)
 // The extension id for the built-in component extension.