Remove CreatePlatformFile from file_util_proxy

base/files/file_util_proxy_unittest.cc

Index: base/files/file_util_proxy_unittest.cc
diff --git a/base/files/file_util_proxy_unittest.cc b/base/files/file_util_proxy_unittest.cc
index 8d8c8eb2708e287f963894902604bf306af2495f..4fa68902a80ef297edaa09a92621d80b398aabcb 100644
--- a/base/files/file_util_proxy_unittest.cc
+++ b/base/files/file_util_proxy_unittest.cc
@@ -88,11 +88,10 @@ class FileUtilProxyTest : public testing::Test {
   PlatformFile GetTestPlatformFile(int flags) {
     if (file_ != kInvalidPlatformFileValue)
       return file_;
-    bool created;
-    PlatformFileError error;
-    file_ = CreatePlatformFile(test_path(), flags, &created, &error);
-    EXPECT_EQ(PLATFORM_FILE_OK, error);
-    EXPECT_NE(kInvalidPlatformFileValue, file_);
+
+    File file(test_path(), flags);
+    EXPECT_TRUE(file.IsValid());
+    file_ = file.TakePlatformFile();
     return file_;
   }