Update UKM network annotations after Unity launch on ChromeOS

The network annotation contained a special description for ChromeOS that
is no longer accurate since Unity launch in M78.

Bug: 951781
Change-Id: I56dffbd46cc0bdf8084e6e48e202c82faace726c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1816541Reviewed-by: Ramin Halavati <rhalavati@chromium.org>
Reviewed-by: Robert Kaplow <rkaplow@chromium.org>
Commit-Queue: Alex Ilin <alexilin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#709842}

components/metrics/net/net_metrics_log_uploader.cc

@@ -102,8 +102,6 @@ net::NetworkTrafficAnnotationTag GetNetworkTrafficAnnotation(
         })");
   }
   DCHECK_EQ(service_type, metrics::MetricsLogUploader::UKM);
-  // TODO(https://crbug.com/951781): Update this annotation once Unity is
-  // enabled on ChromeOS by default.
   return net::DefineNetworkTrafficAnnotation("metrics_report_ukm", R"(
       semantics {
         sender: "Metrics UKM Log Uploader"
@@ -127,19 +125,13 @@ net::NetworkTrafficAnnotationTag GetNetworkTrafficAnnotation(
       policy {
         cookies_allowed: NO
         setting:
-          "On ChromeOS, users can enable or disable this feature by disabling "
-          "'Automatically send diagnostic and usage data to Google' in "
-          "Chrome's settings under Advanced Settings, Privacy. This is only "
-          "enabled if all active profiles have History Sync enabled without a "
-          "Sync passphrase. "
-          "On all other platforms, users can enable or disable this feature by "
-          "disabling 'Make searches and browsing better' in Chrome's settings "
-          "under Advanced Settings, Privacy. This has to be enabled for all "
-          "active profiles. This is only enabled if the user has "
-          "'Help improve Chrome's features and performance' enabled in the "
-          "same settings menu. "
-          "On all platforms, information about the installed extensions is "
-          "sent only if Extension Sync is enabled."
+          "Users can enable or disable this feature by disabling 'Make "
+          "searches and browsing better' in Chrome's settings under Advanced "
+          "Settings, Privacy. This has to be enabled for all active profiles. "
+          "This is only enabled if the user has 'Help improve Chrome's "
+          "features and performance' enabled in the same settings menu. "
+          "Information about the installed extensions is sent only if "
+          "Extension Sync is enabled."
         chrome_policy {
           MetricsReportingEnabled {
             policy_options {mode: MANDATORY}

tools/traffic_annotation/summary/annotations.xml

@@ -147,7 +147,7 @@ Refer to README.md for content description and update process.
  <item id="logo_service" hash_code="35473769" type="0" content_hash_code="20271299" os_list="linux,windows" file_path="components/search_provider_logos/logo_service_impl.cc"/>
  <item id="logo_tracker" hash_code="36859107" type="0" deprecated="2018-12-07" content_hash_code="67588075" file_path=""/>
  <item id="lookup_single_password_leak" hash_code="16927377" type="0" content_hash_code="12158296" os_list="linux,windows" file_path="components/password_manager/core/browser/leak_detection/leak_detection_request.cc"/>
- <item id="metrics_report_ukm" hash_code="727478" type="0" content_hash_code="102972932" os_list="linux,windows" file_path="components/metrics/net/net_metrics_log_uploader.cc"/>
+ <item id="metrics_report_ukm" hash_code="727478" type="0" content_hash_code="8746987" os_list="linux,windows" file_path="components/metrics/net/net_metrics_log_uploader.cc"/>
  <item id="metrics_report_uma" hash_code="727528" type="0" content_hash_code="10176197" os_list="linux,windows" file_path="components/metrics/net/net_metrics_log_uploader.cc"/>
  <item id="mirroring_get_setup_info" hash_code="78447809" type="0" content_hash_code="112561099" os_list="linux,windows" file_path="components/mirroring/service/session_monitor.cc"/>
  <item id="missing" hash_code="77012883" type="0" reserved="1" os_list="linux,windows" file_path=""/>