Perma-launch Client Hint Headers (#1839)

Remove dependency on persistent settings to control the addition of
headers.

b/285656784

(cherry picked from commit e901c3d)

cobalt/h5vcc/h5vcc_settings.cc

@@ -50,7 +50,6 @@ bool H5vccSettings::Set(const std::string& name, SetValueType value) const {
   const char kMediaPrefix[] = "Media.";
   const char kMediaCodecBlockList[] = "MediaCodecBlockList";
   const char kNavigatorUAData[] = "NavigatorUAData";
-  const char kClientHintHeaders[] = "ClientHintHeaders";
   const char kQUIC[] = "QUIC";
 
 #if SB_IS(EVERGREEN)
@@ -81,22 +80,6 @@ bool H5vccSettings::Set(const std::string& name, SetValueType value) const {
     return true;
   }
 
-  if (name.compare(kClientHintHeaders) == 0 && value.IsType<int32>()) {
-    if (!persistent_settings_) {
-      return false;
-    } else {
-      persistent_settings_->SetPersistentSetting(
-          network::kClientHintHeadersEnabledPersistentSettingsKey,
-          std::make_unique<base::Value>(value.AsType<int32>()));
-      // Tell NetworkModule (if exists) to re-query persistent settings.
-      if (network_module_) {
-        network_module_
-            ->SetEnableClientHintHeadersFlagsFromPersistentSettings();
-      }
-      return true;
-    }
-  }
-
   if (name.compare(kQUIC) == 0 && value.IsType<int32>()) {
     if (!persistent_settings_) {
       return false;

cobalt/network/network_module.cc

@@ -113,18 +113,6 @@ void NetworkModule::SetEnableQuicFromPersistentSettings() {
   }
 }
 
-void NetworkModule::SetEnableClientHintHeadersFlagsFromPersistentSettings() {
-  // Called on initialization and when the persistent setting is changed.
-  // If persistent setting is not set, will default to
-  // kCallTypeLoader | kCallTypeXHR.
-  if (options_.persistent_settings != nullptr) {
-    enable_client_hint_headers_flags_.store(
-        options_.persistent_settings->GetPersistentSettingAsInt(
-            kClientHintHeadersEnabledPersistentSettingsKey,
-            (kCallTypeLoader | kCallTypeXHR)));
-  }
-}
-
 void NetworkModule::EnsureStorageManagerStarted() {
   DCHECK(storage_manager_);
   storage_manager_->EnsureStarted();
@@ -143,8 +131,6 @@ void NetworkModule::Initialize(const std::string& user_agent_string,
   http_user_agent_settings_.reset(new net::StaticHttpUserAgentSettings(
       options_.preferred_language, user_agent_string));
 
-  SetEnableClientHintHeadersFlagsFromPersistentSettings();
-
 #if defined(ENABLE_DEBUG_COMMAND_LINE_SWITCHES)
   base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
 
@@ -244,7 +230,7 @@ void NetworkModule::OnCreate(base::WaitableEvent* creation_event) {
 
 void NetworkModule::AddClientHintHeaders(
     net::URLFetcher& url_fetcher, ClientHintHeadersCallType call_type) const {
-  if (enable_client_hint_headers_flags_.load() & call_type) {
+  if (kEnabledClientHintHeaders & call_type) {
     for (const auto& header : client_hint_headers_) {
       url_fetcher.AddExtraRequestHeader(header);
     }

cobalt/network/network_module.h

@@ -49,7 +49,7 @@ namespace cobalt {
 namespace network {
 
 // Used to differentiate type of network call for Client Hint Headers.
-// Values correspond to bit masks against |enable_client_hint_headers_flags_|.
+// Values correspond to bit masks against |kEnabledClientHintHeaders|.
 enum ClientHintHeadersCallType : int32_t {
   kCallTypeLoader = (1u << 0),
   kCallTypeMedia = (1u << 1),
@@ -59,11 +59,10 @@ enum ClientHintHeadersCallType : int32_t {
   kCallTypeXHR = (1u << 5),
 };
 
-const char kQuicEnabledPersistentSettingsKey[] = "QUICEnabled";
+// Determines which type of network calls should include Client Hint Headers.
+constexpr int32_t kEnabledClientHintHeaders = (kCallTypeLoader | kCallTypeXHR);
 
-// Holds bit mask flag, read into |enable_client_hint_headers_flags_|.
-const char kClientHintHeadersEnabledPersistentSettingsKey[] =
-    "clientHintHeadersEnabled";
+const char kQuicEnabledPersistentSettingsKey[] = "QUICEnabled";
 
 class NetworkSystem;
 // NetworkModule wraps various networking-related components such as
@@ -132,9 +131,6 @@ class NetworkModule : public base::MessageLoop::DestructionObserver {
 
   void SetEnableQuicFromPersistentSettings();
 
-  // Checks persistent settings to determine if Client Hint Headers are enabled.
-  void SetEnableClientHintHeadersFlagsFromPersistentSettings();
-
   // Adds the Client Hint Headers to the provided URLFetcher if enabled.
   void AddClientHintHeaders(net::URLFetcher& url_fetcher,
                             ClientHintHeadersCallType call_type) const;
@@ -154,7 +150,6 @@ class NetworkModule : public base::MessageLoop::DestructionObserver {
   std::unique_ptr<network_bridge::NetPoster> CreateNetPoster();
 
   std::vector<std::string> client_hint_headers_;
-  starboard::atomic_int32_t enable_client_hint_headers_flags_;
   std::unique_ptr<storage::StorageManager> storage_manager_;
   std::unique_ptr<base::Thread> thread_;
   std::unique_ptr<URLRequestContext> url_request_context_;