rm DataCompressionProxyHoldback Field Trial code

This code is complicating changing the feature, so time to remove it!

Bug: 1048736
Change-Id: Ia410d07f5ae16db540159a2d4b46aaec1731e15e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2037814Reviewed-by: Tarun Bansal <tbansal@chromium.org>
Commit-Queue: Robert Ogden <robertogden@chromium.org>
Cr-Commit-Position: refs/heads/master@{#738364}

chrome/browser/data_reduction_proxy/data_reduction_proxy_settings_unittest_android.cc

@@ -333,8 +333,9 @@ TEST_F(DataReductionProxySettingsAndroidTest,
 
 TEST_F(DataReductionProxySettingsAndroidTest,
        MaybeRewriteWebliteUrlWithHoldbackEnabled) {
-  ASSERT_TRUE(base::FieldTrialList::CreateFieldTrial(
-      "DataCompressionProxyHoldback", "Enabled"));
+  base::test::ScopedFeatureList scoped_feature_list;
+  scoped_feature_list.InitAndEnableFeature(
+      data_reduction_proxy::features::kDataReductionProxyHoldback);
 
   Init();
   drp_test_context()->EnableDataReductionProxyWithSecureProxyCheckSuccess();
@@ -343,7 +344,7 @@ TEST_F(DataReductionProxySettingsAndroidTest,
             MaybeRewriteWebliteUrlAsUTF8(
                 "http://googleweblight.com/i?u=http://example.com/"));
 
-  // DataCompressionProxyHoldback should not affect https webpages.
+  // DataReductionProxyHoldback should not affect https webpages.
   EXPECT_EQ("https://example.com/",
             MaybeRewriteWebliteUrlAsUTF8(
                 "https://googleweblight.com/i?u=https://example.com/"));

components/data_reduction_proxy/core/browser/data_reduction_proxy_config_unittest.cc

@@ -213,8 +213,9 @@ class DataReductionProxyConfigTest : public testing::Test {
 };
 
 TEST_F(DataReductionProxyConfigTest, TestReloadConfigHoldback) {
-  ASSERT_TRUE(base::FieldTrialList::CreateFieldTrial(
-      "DataCompressionProxyHoldback", "Enabled"));
+  base::test::ScopedFeatureList scoped_feature_list;
+  scoped_feature_list.InitAndEnableFeature(
+      features::kDataReductionProxyHoldback);
 
   const net::ProxyServer kHttpsProxy = net::ProxyServer::FromURI(
       "https://secure_origin.net:443", net::ProxyServer::SCHEME_HTTP);

components/data_reduction_proxy/core/browser/data_reduction_proxy_service_unittest.cc

@@ -12,6 +12,7 @@
 #include "base/metrics/field_trial.h"
 #include "base/run_loop.h"
 #include "base/strings/string_number_conversions.h"
+#include "base/test/scoped_feature_list.h"
 #include "base/time/default_clock.h"
 #include "base/time/time.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_config.h"
@@ -22,6 +23,7 @@
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_request_options.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_test_utils.h"
 #include "components/data_reduction_proxy/core/browser/network_properties_manager.h"
+#include "components/data_reduction_proxy/core/common/data_reduction_proxy_features.h"
 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_headers.h"
 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_params.h"
 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_params_test_utils.h"
@@ -130,8 +132,10 @@ TEST_F(DataReductionProxyServiceTest, TestResetBadProxyListOnDisableDataSaver) {
 }
 
 TEST_F(DataReductionProxyServiceTest, HoldbackConfiguresProxies) {
-  ASSERT_TRUE(base::FieldTrialList::CreateFieldTrial(
-      "DataCompressionProxyHoldback", "Enabled"));
+  base::test::ScopedFeatureList scoped_feature_list;
+  scoped_feature_list.InitAndEnableFeature(
+      features::kDataReductionProxyHoldback);
+
   std::unique_ptr<DataReductionProxyTestContext> drp_test_context =
       DataReductionProxyTestContext::Builder()
           .SkipSettingsInitialization()

components/data_reduction_proxy/core/common/data_reduction_proxy_params.cc

@@ -100,16 +100,8 @@ bool IsIncludedInFREPromoFieldTrial() {
 }
 
 bool IsIncludedInHoldbackFieldTrial() {
-  // For now, DRP can be disabled using either the field trial or the feature.
-  // New server configs should use the feature capability.
-  // TODO(tbansal): Remove the field trial code.
   return base::FeatureList::IsEnabled(
-             data_reduction_proxy::features::kDataReductionProxyHoldback) ||
-         IsIncludedInFieldTrial("DataCompressionProxyHoldback");
-}
-
-std::string HoldbackFieldTrialGroup() {
-  return base::FieldTrialList::FindFullName("DataCompressionProxyHoldback");
+      data_reduction_proxy::features::kDataReductionProxyHoldback);
 }
 
 bool ForceEnableClientConfigServiceForAllDataSaverUsers() {

components/data_reduction_proxy/core/common/data_reduction_proxy_params_unittest.cc

@@ -294,29 +294,6 @@ TEST_F(DataReductionProxyParamsTest, QuicEnableNonCoreProxies) {
   }
 }
 
-TEST_F(DataReductionProxyParamsTest, HoldbackEnabledFieldTrial) {
-  const struct {
-    std::string trial_group_name;
-    bool expected_enabled;
-  } tests[] = {
-      {"Enabled", true},
-      {"Enabled_Control", true},
-      {"Disabled", false},
-      {"enabled", false},
-  };
-
-  for (const auto& test : tests) {
-    base::test::ScopedFeatureList scoped_feature_list;
-    scoped_feature_list.Init();
-
-    ASSERT_TRUE(base::FieldTrialList::CreateFieldTrial(
-        "DataCompressionProxyHoldback", test.trial_group_name));
-    EXPECT_EQ(test.trial_group_name, params::HoldbackFieldTrialGroup());
-    EXPECT_EQ(test.expected_enabled, params::IsIncludedInHoldbackFieldTrial())
-        << test.trial_group_name;
-  }
-}
-
 TEST_F(DataReductionProxyParamsTest, PromoFieldTrial) {
   const struct {
     std::string trial_group_name;