Move PathExists to base namespace.

chrome/common/extensions/unpacker.cc

Index: chrome/common/extensions/unpacker.cc
diff --git a/chrome/common/extensions/unpacker.cc b/chrome/common/extensions/unpacker.cc
index 336a7d56908f502c3086fcbe98c1eb3796747a40..dfd1e317b2d8fe97f9d2f3305f761a42466228fc 100644
--- a/chrome/common/extensions/unpacker.cc
+++ b/chrome/common/extensions/unpacker.cc
@@ -46,7 +46,7 @@ const int kMaxImageCanvas = 4096 * 4096;
 SkBitmap DecodeImage(const base::FilePath& path) {
   // Read the file from disk.
   std::string file_contents;
-  if (!file_util::PathExists(path) ||
+  if (!base::PathExists(path) ||
       !file_util::ReadFileToString(path, &file_contents)) {
     return SkBitmap();
   }
@@ -104,7 +104,7 @@ Unpacker::~Unpacker() {
 base::DictionaryValue* Unpacker::ReadManifest() {
   base::FilePath manifest_path =
       temp_install_dir_.Append(kManifestFilename);
-  if (!file_util::PathExists(manifest_path)) {
+  if (!base::PathExists(manifest_path)) {
     SetError(errors::kInvalidManifest);
     return NULL;
   }