Move ReadFileToString to the base namespace.

chrome/test/chromedriver/util_unittest.cc

Index: chrome/test/chromedriver/util_unittest.cc
diff --git a/chrome/test/chromedriver/util_unittest.cc b/chrome/test/chromedriver/util_unittest.cc
index a710fb58883930cb1297d81f20b530dddcff37e4..85e469e320db5ec15099c9c1dd601bc28e66dc43 100644
--- a/chrome/test/chromedriver/util_unittest.cc
+++ b/chrome/test/chromedriver/util_unittest.cc
@@ -26,7 +26,7 @@ TEST(UnzipSoleFile, Entry) {
   Status status = UnzipSoleFile(temp_dir.path(), data, &file);
   ASSERT_EQ(kOk, status.code()) << status.message();
   std::string contents;
-  ASSERT_TRUE(file_util::ReadFileToString(file, &contents));
+  ASSERT_TRUE(base::ReadFileToString(file, &contents));
   ASSERT_STREQ("COW\n", contents.c_str());
 }
 
@@ -45,6 +45,6 @@ TEST(UnzipSoleFile, Archive) {
   Status status = UnzipSoleFile(temp_dir.path(), data, &file);
   ASSERT_EQ(kOk, status.code()) << status.message();
   std::string contents;
-  ASSERT_TRUE(file_util::ReadFileToString(file, &contents));
+  ASSERT_TRUE(base::ReadFileToString(file, &contents));
   ASSERT_STREQ("COW\n", contents.c_str());
 }