Initial framework setup and skeleton for BackgroundFetchContext

content/browser/background_fetch/background_fetch_data_manager.cc

+// Copyright 2017 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.
+
+#include "content/browser/background_fetch/background_fetch_data_manager.h"
+
+#include "content/browser/background_fetch/background_fetch_context.h"
+#include "content/browser/background_fetch/fetch_request.h"
+
+namespace content {
+
+BackgroundFetchDataManager::BackgroundFetchDataManager(
+    BackgroundFetchContext* background_fetch_context)
+    : background_fetch_context_(background_fetch_context) {
+  DCHECK(background_fetch_context_);
+  // TODO(harkness) Read from persistent storage and recreate requests.
+}
+
+BackgroundFetchDataManager::~BackgroundFetchDataManager() {}
+
+void BackgroundFetchDataManager::CreateRequest(
+    const FetchRequest& fetch_request) {
+  FetchIdentifier id = {fetch_request.origin(), fetch_request.tag()};

[Peter Beverloo, 2017/02/13 18:35:05]

nit: I think you can drop the " = " and call the constructor instead.

[harkness, 2017/02/14 13:52:46]

Done.

+  if (fetch_map_.find(id) != fetch_map_.end()) {
+    DLOG(ERROR) << "Origin " << fetch_request.origin()
+                << " has already created a fetch request with tag "
+                << fetch_request.tag();
+    // TODO(harkness) Figure out how to return errors like this.
+    return;
+  }
+  fetch_map_[id] = fetch_request;
+}
+
+}  // namespace content