[DRP] Consistently use LoFi for an entire page

components/data_reduction_proxy/core/browser/data_reduction_proxy_request_options.cc

Index: components/data_reduction_proxy/core/browser/data_reduction_proxy_request_options.cc
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_request_options.cc b/components/data_reduction_proxy/core/browser/data_reduction_proxy_request_options.cc
index 6a52cdf18446ea1cabf8224b51949a8aadafcf55..b165acad2990bb090d92a7f69eb0054cde629a40 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_request_options.cc
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_request_options.cc
@@ -161,25 +161,26 @@ void DataReductionProxyRequestOptions::UpdateVersion() {
 }
 
 void DataReductionProxyRequestOptions::MayRegenerateHeaderBasedOnLoFi(
-    const net::URLRequest* request) {
+    bool is_using_lofi_mode) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
-  if (!data_reduction_proxy_config_)
-    return;
-
-  bool lofi_now_enabled =
-      !(request && request->load_flags() & net::LOAD_BYPASS_CACHE) &&
-      data_reduction_proxy_config_->ShouldUseLoFiHeaderForRequests();
+  // The Lo-Fi directive should not be added for users in the Lo-Fi field
+  // trial "Control" group. Check that the user is in a group that should
+  // get "q=low".
+  bool lofi_enabled_via_flag_or_field_trial =
+      params::IsLoFiOnViaFlags() || params::IsIncludedInLoFiEnabledFieldTrial();
 
   // Lo-Fi was not enabled, but now is. Add the header option.
-  if (lofi_.empty() && lofi_now_enabled) {
+  if (lofi_.empty() && is_using_lofi_mode &&
+      lofi_enabled_via_flag_or_field_trial) {
     lofi_ = "low";
     RegenerateRequestHeaderValue();
     return;
   }
 
   // Lo-Fi was enabled, but no longer is. Remove the header option.
-  if (!lofi_.empty() && !lofi_now_enabled) {
+  if (!lofi_.empty() &&
+      (!is_using_lofi_mode || !lofi_enabled_via_flag_or_field_trial)) {
     lofi_ = std::string();
     RegenerateRequestHeaderValue();
     return;
@@ -188,7 +189,7 @@ void DataReductionProxyRequestOptions::MayRegenerateHeaderBasedOnLoFi(
   // User was not part of Lo-Fi active control experiment, but now is.
   if (std::find(experiments_.begin(), experiments_.end(),
                 std::string(kLoFiExperimentID)) == experiments_.end() &&
-      data_reduction_proxy_config_->IsInLoFiActiveControlExperiment()) {
+      is_using_lofi_mode && params::IsIncludedInLoFiControlFieldTrial()) {
     experiments_.push_back(kLoFiExperimentID);
     RegenerateRequestHeaderValue();
     DCHECK(std::find(experiments_.begin(), experiments_.end(),
@@ -200,7 +201,7 @@ void DataReductionProxyRequestOptions::MayRegenerateHeaderBasedOnLoFi(
   auto it = std::find(experiments_.begin(), experiments_.end(),
                       std::string(kLoFiExperimentID));
   if (it != experiments_.end() &&
-      !data_reduction_proxy_config_->IsInLoFiActiveControlExperiment()) {
+      (!is_using_lofi_mode || !params::IsIncludedInLoFiControlFieldTrial())) {
     experiments_.erase(it);
     RegenerateRequestHeaderValue();
     DCHECK(std::find(experiments_.begin(), experiments_.end(),
@@ -248,31 +249,34 @@ void DataReductionProxyRequestOptions::RandBytes(void* output,
 void DataReductionProxyRequestOptions::MaybeAddRequestHeader(
     net::URLRequest* request,
     const net::ProxyServer& proxy_server,
-    net::HttpRequestHeaders* request_headers) {
+    net::HttpRequestHeaders* request_headers,
+    bool is_using_lofi_mode) {
   DCHECK(thread_checker_.CalledOnValidThread());
   if (!proxy_server.is_valid())
     return;
   if (proxy_server.is_direct())
     return;
   MaybeAddRequestHeaderImpl(request, proxy_server.host_port_pair(), false,
-                            request_headers);
+                            request_headers, is_using_lofi_mode);
 }
 
 void DataReductionProxyRequestOptions::MaybeAddProxyTunnelRequestHandler(
     const net::HostPortPair& proxy_server,
     net::HttpRequestHeaders* request_headers) {
   DCHECK(thread_checker_.CalledOnValidThread());
-  MaybeAddRequestHeaderImpl(nullptr, proxy_server, true, request_headers);
+  MaybeAddRequestHeaderImpl(nullptr, proxy_server, true, request_headers,
+                            false);
 }
 
 void DataReductionProxyRequestOptions::SetHeader(
     const net::URLRequest* request,
-    net::HttpRequestHeaders* headers) {
+    net::HttpRequestHeaders* headers,
+    bool is_using_lofi_mode) {
   base::Time now = Now();
   // Authorization credentials must be regenerated if they are expired.
   if (!use_assigned_credentials_ && (now > credentials_expiration_time_))
     UpdateCredentials();
-  MayRegenerateHeaderBasedOnLoFi(request);
+  MayRegenerateHeaderBasedOnLoFi(is_using_lofi_mode);
   const char kChromeProxyHeader[] = "Chrome-Proxy";
   std::string header_value;
   if (headers->HasHeader(kChromeProxyHeader)) {
@@ -392,13 +396,14 @@ void DataReductionProxyRequestOptions::MaybeAddRequestHeaderImpl(
     const net::URLRequest* request,
     const net::HostPortPair& proxy_server,
     bool expect_ssl,
-    net::HttpRequestHeaders* request_headers) {
+    net::HttpRequestHeaders* request_headers,
+    bool is_using_lofi_mode) {
   if (proxy_server.IsEmpty())
     return;
   if (data_reduction_proxy_config_->IsDataReductionProxy(proxy_server, NULL) &&
       data_reduction_proxy_config_->UsingHTTPTunnel(proxy_server) ==
           expect_ssl) {
-    SetHeader(request, request_headers);
+    SetHeader(request, request_headers, is_using_lofi_mode);
   }
 }