Allow the component updater framework to control Origin Trials.

chrome/browser/component_updater/origin_trials_component_installer.cc

+// Copyright 2016 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 "chrome/browser/component_updater/origin_trials_component_installer.h"
+
+#include "base/bind.h"
+#include "base/command_line.h"
+#include "base/files/file_path.h"
+#include "base/path_service.h"
+#include "chrome/common/chrome_switches.h"
+#include "components/component_updater/component_updater_paths.h"
+
+// The client-side configuration for the origin trial framework can be
+// overridden by an installed component named 'OriginTrials' (extension id
+// kfoklmclfodeliojeaekpoflbkkhojea. This component currently consists of just a
+// manifest.json file, which can contain a custom key named 'origin-trials'. The
+// value of this key is a dictionary:
+//
+// {
+//   "public-key": "<base64-encoding of replacement public key>",
+//   "disabled-features": [<list of features to disable>],
+//   "revoked-tokens": "<base64-encoded data>"
+// }
+//
+// TODO(iclelland): Implement support for revoked tokens and disabled features.
+//
+// If the component is not present in the user data directory, the default
+// configuration will be used.
+
+namespace component_updater {
+
+namespace {
+
+// Extension id is kfoklmclfodeliojeaekpoflbkkhojea
+const uint8_t kSha256Hash[] = {
+  0xa5, 0xea, 0xbc, 0x2b, 0x5e, 0x34, 0xb8, 0xe9,
+  0x40, 0x4a, 0xfe, 0x5b, 0x1a, 0xa7, 0xe9, 0x40,
+  0xa8, 0xc5, 0xef, 0xa1, 0x9e, 0x20, 0x5a, 0x39,
+  0x73, 0x98, 0x98, 0x0f, 0x7a, 0x76, 0x62, 0xfa
+};
+
+}  // namespace
+
+bool OriginTrialsComponentInstallerTraits::VerifyInstallation(
+    const base::DictionaryValue& manifest,
+    const base::FilePath& install_dir) const {
+  // Test if the "origin-trials" key is present in the manifest.
+  return manifest.HasKey("origin-trials");
+}
+
+bool OriginTrialsComponentInstallerTraits::CanAutoUpdate() const {
+  return true;
+}
+
+bool OriginTrialsComponentInstallerTraits::RequiresNetworkEncryption() const {
+  return true;
+}
+
+bool OriginTrialsComponentInstallerTraits::OnCustomInstall(
+    const base::DictionaryValue& manifest,
+    const base::FilePath& install_dir) {
+  return true;  // nothing to do!

[Sorin Jianu, 2016/04/13 21:17:47]

Comment is not needed. Please start with capital letter if the decision is to
keep the comment anyway.

[iclelland, 2016/04/14 14:30:08]

Removed.

+}
+
+void OriginTrialsComponentInstallerTraits::ComponentReady(
+    const base::Version& version,
+    const base::FilePath& install_dir,
+    std::unique_ptr<base::DictionaryValue> manifest) {
+  // Read the public key from the manifest and set the command line.
+  std::string override_public_key;
+  if (manifest->GetString("origin-trials.public-key", &override_public_key)) {
+    base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
+    command_line->AppendSwitchASCII(switches::kOriginTrialPublicKey,
+                                    override_public_key);
+  }
+}
+
+base::FilePath OriginTrialsComponentInstallerTraits::GetBaseDirectory() const {
+  base::FilePath result;
+  PathService::Get(DIR_ORIGIN_TRIAL_KEYS, &result);
+  return result;
+}
+
+void OriginTrialsComponentInstallerTraits::GetHash(
+    std::vector<uint8_t>* hash) const {
+  if (!hash)
+    return;
+  hash->assign(kSha256Hash,
+               kSha256Hash + arraysize(kSha256Hash));
+}
+
+std::string OriginTrialsComponentInstallerTraits::GetName() const {
+  return "Origin Trials";
+}
+
+std::string OriginTrialsComponentInstallerTraits::GetAp() const {
+  // No additional parameters required; return empty string.

[Sorin Jianu, 2016/04/13 21:17:47]

Comment is not needed, especially the part that follows after ;.

[iclelland, 2016/04/14 14:30:07]

Removed.

+  return std::string();
+}
+
+void RegisterOriginTrialsComponent(ComponentUpdateService* cus,
+                                   const base::FilePath& user_data_dir) {
+  VLOG(1) << "Registering origin trials component.";

[Sorin Jianu, 2016/04/13 21:17:47]

Maybe use a DVLOG if this is needed for debugging, otherwise, our opinion is
that the VLOG here provides little value.

[iclelland, 2016/04/14 14:30:07]

Also removed.

+
+  scoped_ptr<ComponentInstallerTraits> traits(
+      new OriginTrialsComponentInstallerTraits());
+  // |cus| will take ownership of |installer| during installer->Register(cus).
+  DefaultComponentInstaller* installer =
+      new DefaultComponentInstaller(std::move(traits));
+  installer->Register(cus, base::Closure());
+}
+
+}  // namespace component_updater