Enable WCG on Pixel 4 by default

Wide color gamut on Pixel 4 was already enabled by default, but
the rigging was setup as though it wasn't. Part of the feature
roll-out is to mark the feature as enabled-by-default.

This CL mimics that step (but leaves it already enabled-by-default)
by removing the field trial and updating the feature check to
no longer require that field trial.

Bug: 1021181
Change-Id: I556a25b39f667e2e9199fb8d6d9b8f680d97fee0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1992010Reviewed-by: Ilya Sherman <isherman@chromium.org>
Commit-Queue: Chris Blume <cblume@chromium.org>
Cr-Commit-Position: refs/heads/master@{#729638}

chrome/common/chrome_features.cc

@@ -4,7 +4,7 @@
 
 #include "chrome/common/chrome_features.h"
 
-#include <vector>
+#include <array>
 
 #include "base/command_line.h"
 #include "base/no_destructor.h"
@@ -737,23 +737,12 @@ const base::Feature kHeavyAdPrivacyMitigations{
     "HeavyAdPrivacyMitigations", base::FEATURE_ENABLED_BY_DEFAULT};
 
 #if defined(OS_ANDROID)
-const base::Feature kUseDisplayWideColorGamut{"UseDisplayWideColorGamut",
-                                              base::FEATURE_ENABLED_BY_DEFAULT};
-
 bool UseDisplayWideColorGamut() {
   auto compute_use_display_wide_color_gamut = []() {
-    // Enabled this feature for devices listed in "enabled_models" field trial
-    // param. This is a comma separated list.
-    std::string enabled_models_list = base::GetFieldTrialParamValueByFeature(
-        kUseDisplayWideColorGamut, "enabled_models");
-    if (enabled_models_list.empty())
-      return false;
-
     const char* current_model =
         base::android::BuildInfo::GetInstance()->model();
-    std::vector<std::string> enabled_models =
-        base::SplitString(enabled_models_list, ",", base::KEEP_WHITESPACE,
-                          base::SPLIT_WANT_NONEMPTY);
+    const std::array<std::string, 2> enabled_models = {
+        std::string{"Pixel 4"}, std::string{"Pixel 4 XL"}};
     for (const std::string& model : enabled_models) {
       if (model == current_model)
         return true;

testing/variations/fieldtrial_testing_config.json

@@ -567,24 +567,6 @@
             ]
         }
     ],
-    "AndroidWideColorGamut": [
-        {
-            "platforms": [
-                "android"
-            ],
-            "experiments": [
-                {
-                    "name": "UseDisplayWideColorGamut",
-                    "params": {
-                        "enabled_models": "Pixel 4,Pixel 4 XL"
-                    },
-                    "enable_features": [
-                        "UseDisplayWideColorGamut"
-                    ]
-                }
-            ]
-        }
-    ],
     "AppLauncherRefresh": [
         {
             "platforms": [