[Variations] Bring variations_http_header_provider to variations component

chrome/browser/metrics/variations/proto/BUILD.gn

Index: chrome/browser/metrics/variations/proto/BUILD.gn
diff --git a/chrome/browser/metrics/variations/proto/BUILD.gn b/chrome/browser/metrics/variations/proto/BUILD.gn
deleted file mode 100644
index 732e86f2954139b2e5ce73a27c35d5fba899ee5a..0000000000000000000000000000000000000000
--- a/chrome/browser/metrics/variations/proto/BUILD.gn
+++ /dev/null
@@ -1,12 +0,0 @@
-# Copyright 2014 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-import("//third_party/protobuf/proto_library.gni")
-
-# GYP version: chrome/chrome_browser.gypi:variations_proto
-proto_library("proto") {
-  sources = [
-    "chrome_experiments.proto",
-  ]
-}