Split up ios/web:test_support.

ios/web/public/test/response_providers/file_based_response_provider.mm

-// Copyright 2015 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 "ios/web/public/test/response_providers/file_based_response_provider.h"
-
-#include "base/files/file_path.h"
-#include "base/strings/sys_string_conversions.h"
-#import "ios/third_party/gcdwebserver/src/GCDWebServer/Responses/GCDWebServerFileResponse.h"
-
-namespace web {
-
-FileBasedResponseProvider::FileBasedResponseProvider(const base::FilePath& path)
-    : response_provider_impl_(new FileBasedResponseProviderImpl(path)) {
-}
-
-FileBasedResponseProvider::~FileBasedResponseProvider() {
-}
-
-bool FileBasedResponseProvider::CanHandleRequest(const Request& request) {
-  return response_provider_impl_->CanHandleRequest(request);
-}
-
-GCDWebServerResponse* FileBasedResponseProvider::GetGCDWebServerResponse(
-    const Request& request) {
-  const base::FilePath file_path =
-      response_provider_impl_->BuildTargetPath(request.url);
-  NSString* path = base::SysUTF8ToNSString(file_path.value());
-  return [GCDWebServerFileResponse responseWithFile:path];
-}
-
-}  // namespace web