Remove enable_media_router.

chrome/browser/extensions/BUILD.gn

Index: chrome/browser/extensions/BUILD.gn
diff --git a/chrome/browser/extensions/BUILD.gn b/chrome/browser/extensions/BUILD.gn
index 0ffd8e328c37f9cf57e6d3b69ed8b4392807f034..d7129d88b83f13dc5dd7fcefe29058ecf29de8b9 100644
--- a/chrome/browser/extensions/BUILD.gn
+++ b/chrome/browser/extensions/BUILD.gn
@@ -831,6 +831,7 @@ static_library("extensions") {
     "//chrome/app/theme:theme_resources",
     "//chrome/app/vector_icons",
     "//chrome/browser/devtools",
+    "//chrome/browser/media/router",
     "//chrome/common",
     "//chrome/common/extensions/api:api_registration",
     "//chrome/common/extensions/api:extensions_features",
@@ -932,10 +933,6 @@ static_library("extensions") {
     "//url",
   ]
 
-  if (enable_media_router) {
-    deps += [ "//chrome/browser/media/router" ]
-  }
-
   if (!is_chromeos) {
     sources += [ "chrome_kiosk_delegate.cc" ]
   }