[Doodle] Introduce a DoodleService

components/doodle/doodle_types.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 "components/doodle/doodle_types.h"
+
+namespace doodle {
+
+bool DoodleImage::operator==(const DoodleImage& other) const {
+  return url == other.url && height == other.height && width == other.width &&
+         is_animated_gif == other.is_animated_gif && is_cta == other.is_cta;
+}
+
+bool DoodleImage::operator!=(const DoodleImage& other) const {
+  return !(*this == other);
+}
+
+bool DoodleConfig::IsEquivalent(const DoodleConfig& other) const {
+  // Note: This compares all fields except for |expiry_date|. The reason is that
+  // |expiry_date| gets computed as "now + time_to_live", so when an identical

[vitaliii, 2017/02/28 11:37:18]

This feels like too many implementation details.
Why not "|expiry_date| depends on when fetch happens, so when an identical
config gets re-fetched, the expiry date will be different."

[Marc Treib, 2017/02/28 13:06:49]

"too many implementation details" is kinda true, but IMO this is weird and
unexpected enough that it deserves an explicit, detailed comment.
This isn't really a great place for it, but I don't know where else to put it.

Longer-term, I'd hope to get rid of the expiry_time member completely, since
it's not really needed here. See the TODO in the header.

+  // config gets re-fetched, the expiry date will generally end up slightly
+  // different.
+  return doodle_type == other.doodle_type && alt_text == other.alt_text &&
+         interactive_html == other.interactive_html &&
+         search_url == other.search_url && target_url == other.target_url &&
+         fullpage_interactive_url == other.fullpage_interactive_url &&
+         large_image == other.large_image &&
+         large_cta_image == other.large_cta_image &&
+         transparent_large_image == other.transparent_large_image;
+}
+
+}  // namespace doodle