Move ReadFileToString to the base namespace.

chrome/browser/ui/find_bar/find_bar_host_browsertest.cc

Index: chrome/browser/ui/find_bar/find_bar_host_browsertest.cc
diff --git a/chrome/browser/ui/find_bar/find_bar_host_browsertest.cc b/chrome/browser/ui/find_bar/find_bar_host_browsertest.cc
index c4030c8e24e6d49b9c7cd9197ba3e2f1e19b44ff..5ea3c32de6a37931923d8fdfef0aa20025a88442 100644
--- a/chrome/browser/ui/find_bar/find_bar_host_browsertest.cc
+++ b/chrome/browser/ui/find_bar/find_bar_host_browsertest.cc
@@ -404,7 +404,7 @@ IN_PROC_BROWSER_TEST_F(FindInPageControllerTest, FindLongString) {
       base::FilePath().AppendASCII("find_in_page"),
       base::FilePath().AppendASCII("LongFind.txt"));
   std::string query;
-  file_util::ReadFileToString(path, &query);
+  base::ReadFileToString(path, &query);
   std::wstring search_string = UTF8ToWide(query);
   EXPECT_EQ(1,
             FindInPageWchar(web_contents, search_string.c_str(),
@@ -467,7 +467,7 @@ IN_PROC_BROWSER_TEST_F(FindInPageControllerTest, FindWholeFileContent) {
   ui_test_utils::NavigateToURL(browser(), net::FilePathToFileURL(path));
 
   std::string query;
-  file_util::ReadFileToString(path, &query);
+  base::ReadFileToString(path, &query);
   std::wstring search_string = UTF8ToWide(query);
   EXPECT_EQ(1,
             FindInPageWchar(web_contents, search_string.c_str(),