Add LogoTracker to fetch search providers' logos.

The LogoTracker keeps track of the logo for a search provider. The logo
is downloaded, cached on disk, and periodically revalidated.

This code lives inside a component (search_provider_logos) so it can be
used on both Android and iOS.

BUG=178922
NOTRY=true

Review URL: https://codereview.chromium.org/162373002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@267314 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 70 insertions, 0 deletions

diff --git a/components/search_provider_logos/logo_common.h b/components/search_provider_logos/logo_common.h
new file mode 100644
index 0000000..207026b
--- /dev/null
+++ b/components/search_provider_logos/logo_common.h
@@ -0,0 +1,70 @@
+// 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.
+
+#ifndef COMPONENTS_SEARCH_PROVIDER_LOGOS_LOGO_COMMON_H_
+#define COMPONENTS_SEARCH_PROVIDER_LOGOS_LOGO_COMMON_H_
+
+#include <string>
+
+#include "base/memory/ref_counted.h"
+#include "base/memory/ref_counted_memory.h"
+#include "base/time/time.h"
+#include "third_party/skia/include/core/SkBitmap.h"
+
+namespace search_provider_logos {
+
+// The maximum number of milliseconds that a logo can be cached.
+extern const int64 kMaxTimeToLiveMS;
+
+struct LogoMetadata {
+  LogoMetadata();
+  ~LogoMetadata();
+
+  // For use by the client ----------------------------------------------------
+
+  // The URL to load when the logo is clicked.
+  std::string on_click_url;
+  // The accessibility text for the logo.
+  std::string alt_text;
+  // The mime type of the logo image.
+  std::string mime_type;
+
+  // For use by LogoTracker ---------------------------------------------------
+
+  // The URL from which the logo was downloaded (without the fingerprint param).
+  std::string source_url;
+  // A fingerprint (i.e. hash) identifying the logo. Used when revalidating the
+  // logo with the server.
+  std::string fingerprint;
+  // Whether the logo can be shown optimistically after it's expired while a
+  // fresh logo is being downloaded.
+  bool can_show_after_expiration;
+  // When the logo expires. After this time, the logo will not be used and will
+  // be deleted.
+  base::Time expiration_time;
+};
+
+struct EncodedLogo {
+  EncodedLogo();
+  ~EncodedLogo();
+
+  // The jpeg- or png-encoded image.
+  scoped_refptr<base::RefCountedString> encoded_image;
+  // Metadata about the logo.
+  LogoMetadata metadata;
+};
+
+struct Logo {
+  Logo();
+  ~Logo();
+
+  // The logo image.
+  SkBitmap image;
+  // Metadata about the logo.
+  LogoMetadata metadata;
+};
+
+}  // namespace search_provider_logos
+
+#endif  // COMPONENTS_SEARCH_PROVIDER_LOGOS_LOGO_COMMON_H_