Deprecate more old filepath functions.

printing/image.cc

Index: printing/image.cc
diff --git a/printing/image.cc b/printing/image.cc
index d12d3d602b2fa818422c8163d8f187f48777ea95..77f5d5ef610d0e6495c0c5f21e2d7fe24ad5acd0 100644
--- a/printing/image.cc
+++ b/printing/image.cc
@@ -60,16 +60,15 @@ class DisableFontSmoothing {
 
 namespace printing {
 
-Image::Image(const std::wstring& filename)
+Image::Image(const FilePath& path)
     : row_length_(0),
       ignore_alpha_(true) {
   std::string data;
-  file_util::ReadFileToString(filename, &data);
-  std::wstring ext = file_util::GetFileExtensionFromPath(filename);
+  file_util::ReadFileToString(path, &data);
   bool success = false;
-  if (LowerCaseEqualsASCII(ext, "png")) {
+  if (path.MatchesExtension(FILE_PATH_LITERAL(".png"))) {
     success = LoadPng(data);
-  } else if (LowerCaseEqualsASCII(ext, "emf")) {
+  } else if (path.MatchesExtension(FILE_PATH_LITERAL(".emf"))) {
     success = LoadMetafile(data);
   } else {
     DCHECK(false);