ungoogled-chromium: inherit upstream's build flags

This ensures that our build flags for ungoogled-chromium will remain
up-to-date with upstream's defaults (also important for avoiding build
errors).

Co-authored-by: Michael Weiss <dev.primeos@gmail.com>

pkgs/applications/networking/browsers/chromium/common.nix

@@ -287,24 +287,8 @@ let
     } // optionalAttrs pulseSupport {
       use_pulseaudio = true;
       link_pulseaudio = true;
-    } // optionalAttrs ungoogled {
-      chrome_pgo_phase = 0;
-      enable_hangout_services_extension = false;
-      enable_js_type_check = false;
-      enable_mdns = false;
-      enable_one_click_signin = false;
-      enable_reading_list = false;
-      enable_remoting = false;
-      enable_reporting = false;
-      enable_service_discovery = false;
-      exclude_unwind_tables = true;
-      google_api_key = "";
-      google_default_client_id = "";
-      google_default_client_secret = "";
-      safe_browsing_mode = 0;
-      use_official_google_api_keys = false;
-      use_unofficial_version_number = false;
-    } // (extraAttrs.gnFlags or {}));
+    } // optionalAttrs ungoogled (importTOML ./ungoogled-flags.toml)
+    // (extraAttrs.gnFlags or {}));
 
     configurePhase = ''
       runHook preConfigure

pkgs/applications/networking/browsers/chromium/ungoogled-flags.toml

@@ -0,0 +1,23 @@
+build_with_tflite_lib=false
+chrome_pgo_phase=0
+clang_use_chrome_plugins=false
+disable_fieldtrial_testing_config=true
+enable_hangout_services_extension=false
+enable_js_type_check=false
+enable_mdns=false
+enable_mse_mpeg2ts_stream_parser=true
+enable_nacl=false
+enable_one_click_signin=false
+enable_reading_list=false
+enable_remoting=false
+enable_reporting=false
+enable_service_discovery=false
+enable_widevine=true
+exclude_unwind_tables=true
+google_api_key=""
+google_default_client_id=""
+google_default_client_secret=""
+safe_browsing_mode=0
+treat_warnings_as_errors=false
+use_official_google_api_keys=false
+use_unofficial_version_number=false

pkgs/applications/networking/browsers/chromium/update.py

@@ -24,6 +24,7 @@ DEB_URL = 'https://dl.google.com/linux/chrome/deb/pool/main/g'
 BUCKET_URL = 'https://commondatastorage.googleapis.com/chromium-browser-official'
 
 JSON_PATH = dirname(abspath(__file__)) + '/upstream-info.json'
+UNGOOGLED_FLAGS_PATH = dirname(abspath(__file__)) + '/ungoogled-flags.toml'
 COMMIT_MESSAGE_SCRIPT = dirname(abspath(__file__)) + '/get-commit-message.py'
 
 
@@ -108,6 +109,12 @@ def get_latest_ungoogled_chromium_build():
     }
 
 
+def get_ungoogled_chromium_gn_flags(revision):
+    """Returns ungoogled-chromium's GN build flags for the given revision."""
+    gn_flags_url = f'https://raw.githubusercontent.com/Eloston/ungoogled-chromium/{revision}/flags.gn'
+    return urlopen(gn_flags_url).read().decode()
+
+
 def channel_name_to_attr_name(channel_name):
     """Maps a channel name to the corresponding main Nixpkgs attribute name."""
     if channel_name == 'stable':
@@ -208,6 +215,8 @@ with urlopen(HISTORY_URL) as resp:
                 'rev': build['ungoogled_tag'],
                 'sha256': nix_prefetch_git(ungoogled_repo_url, build['ungoogled_tag'])['sha256']
             }
+            with open(UNGOOGLED_FLAGS_PATH, 'w') as out:
+                out.write(get_ungoogled_chromium_gn_flags(build['ungoogled_tag']))
 
         channels[channel_name] = channel
 
@@ -227,6 +236,8 @@ if len(sys.argv) == 2 and sys.argv[1] == '--commit':
             if channel_name == 'stable':
                 body = subprocess.check_output([COMMIT_MESSAGE_SCRIPT, version_new]).decode('utf-8')
                 commit_message += '\n\n' + body
+            elif channel_name == 'ungoogled-chromium':
+                subprocess.run(['git', 'add', UNGOOGLED_FLAGS_PATH], check=True)
             subprocess.run(['git', 'add', JSON_PATH], check=True)
             subprocess.run(['git', 'commit', '--file=-'], input=commit_message.encode(), check=True)
 else: