Convert some component source sets to static library

components/memory_coordinator/browser/BUILD.gn

 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-source_set("browser") {
+static_library("browser") {
   sources = [
     "memory_coordinator.cc",
     "memory_coordinator.h",
   ]
 
   deps = [
     "//base",
     "//components/memory_coordinator/public/interfaces",
   ]
 
   public_deps = [
     "//components/memory_coordinator/common",
   ]
 }