Move chrome.fileSystem implementation to //extensions

chrome/browser/extensions/api/file_system/file_system_apitest.cc

Index: chrome/browser/extensions/api/file_system/file_system_apitest.cc
diff --git a/chrome/browser/extensions/api/file_system/file_system_apitest.cc b/chrome/browser/extensions/api/file_system/file_system_apitest.cc
index abd1da1beea317f386e746161643ea03f3ad61c4..fde936c0479eaa38e505770f623c5f3c9e4cdc66 100644
--- a/chrome/browser/extensions/api/file_system/file_system_apitest.cc
+++ b/chrome/browser/extensions/api/file_system/file_system_apitest.cc
@@ -10,14 +10,16 @@
 #include "base/threading/thread_restrictions.h"
 #include "build/build_config.h"
 #include "chrome/browser/apps/app_browsertest_util.h"
-#include "chrome/browser/extensions/api/file_system/file_system_api.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/chrome_paths.h"
+#include "extensions/browser/api/file_system/file_system_api.h"
 #include "extensions/browser/api/file_system/saved_file_entry.h"
 #include "extensions/browser/extension_prefs.h"
 #include "extensions/browser/extension_registry.h"
 #include "extensions/browser/extension_registry_observer.h"
 
+// TODO(michaelpg): Port these tests to app_shell: crbug.com/505926.
+
 namespace content {
 class BrowserContext;
 }