Begin the first small step towards using FilePath everywhere:

chrome/browser/download/save_page_uitest.cc

Index: chrome/browser/download/save_page_uitest.cc
diff --git a/chrome/browser/download/save_page_uitest.cc b/chrome/browser/download/save_page_uitest.cc
index 4e9fca60a0262db33f05d82943debf2d3a733e22..551c335f5074b902800cfd9f5b3eb6737916f176 100644
--- a/chrome/browser/download/save_page_uitest.cc
+++ b/chrome/browser/download/save_page_uitest.cc
@@ -43,7 +43,7 @@ class SavePageTest : public UITest {
       EXPECT_TRUE(file_util::GetFileSize(client_file, &client_file_size));
       EXPECT_TRUE(file_util::GetFileSize(server_file_name, &server_file_size));
       EXPECT_EQ(client_file_size, server_file_size);
-      EXPECT_PRED2(file_util::ContentsEqual, client_file, server_file_name);
+      EXPECT_TRUE(file_util::ContentsEqual(client_file, server_file_name));
     }
 
     EXPECT_TRUE(DieFileDie(client_file, false));