Move PathExists to base namespace.

chrome/common/extensions/background_info.cc

Index: chrome/common/extensions/background_info.cc
diff --git a/chrome/common/extensions/background_info.cc b/chrome/common/extensions/background_info.cc
index c82b3a1e228a86f2b8704168d7d1679294884698..8d21f5dafce9cd2fd0466e2cfe931938860c7534 100644
--- a/chrome/common/extensions/background_info.cc
+++ b/chrome/common/extensions/background_info.cc
@@ -264,7 +264,7 @@ bool BackgroundManifestHandler::Validate(
   const std::vector<std::string>& background_scripts =
       extensions::BackgroundInfo::GetBackgroundScripts(extension);
   for (size_t i = 0; i < background_scripts.size(); ++i) {
-    if (!file_util::PathExists(
+    if (!base::PathExists(
             extension->GetResource(background_scripts[i]).GetFilePath())) {
       *error = l10n_util::GetStringFUTF8(
           IDS_EXTENSION_LOAD_BACKGROUND_SCRIPT_FAILED,
@@ -282,7 +282,7 @@ bool BackgroundManifestHandler::Validate(
         extension_file_util::ExtensionURLToRelativeFilePath(
             extensions::BackgroundInfo::GetBackgroundURL(extension));
     const base::FilePath path = extension->GetResource(page_path).GetFilePath();
-    if (path.empty() || !file_util::PathExists(path)) {
+    if (path.empty() || !base::PathExists(path)) {
       *error =
           l10n_util::GetStringFUTF8(
               IDS_EXTENSION_LOAD_BACKGROUND_PAGE_FAILED,