Move most of extension_file_util.cc into extensions/common/file_util.cc

chrome/browser/extensions/requirements_checker_browsertest.cc

Index: chrome/browser/extensions/requirements_checker_browsertest.cc
diff --git a/chrome/browser/extensions/requirements_checker_browsertest.cc b/chrome/browser/extensions/requirements_checker_browsertest.cc
index bc1c6ed75de5e6a0cd78b0b0f8bb1f0fb25f9762..9115aec3ad7e04d4258ca9f9afa1bb12ef7812a9 100644
--- a/chrome/browser/extensions/requirements_checker_browsertest.cc
+++ b/chrome/browser/extensions/requirements_checker_browsertest.cc
@@ -15,10 +15,10 @@
 #include "chrome/browser/extensions/extension_browsertest.h"
 #include "chrome/browser/extensions/requirements_checker.h"
 #include "chrome/common/chrome_paths.h"
-#include "chrome/common/extensions/extension_file_util.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/gpu_data_manager.h"
 #include "extensions/common/extension.h"
+#include "extensions/common/file_util.h"
 #include "gpu/config/gpu_info.h"
 #include "grit/generated_resources.h"
 #include "ui/base/l10n/l10n_util.h"
@@ -35,9 +35,8 @@ class RequirementsCheckerBrowserTest : public ExtensionBrowserTest {
     PathService::Get(chrome::DIR_TEST_DATA, &extension_path);
     extension_path = extension_path.AppendASCII("requirements_checker")
                                    .AppendASCII(extension_dir_name);
-    scoped_refptr<const Extension> extension =
-        extension_file_util::LoadExtension(extension_path, Manifest::UNPACKED,
-                                           0, &load_error);
+    scoped_refptr<const Extension> extension = file_util::LoadExtension(
+        extension_path, Manifest::UNPACKED, 0, &load_error);
     CHECK(load_error.length() == 0u);
     return extension;
   }