Makes chrome://help-app available behind a chrome://flag for official ChromeOS builds.

enums.xml numbers come from the suggested values given by the unit test.
See https://chromium.googlesource.com/chromium/src/tools/+/refs/heads/master/metrics/histograms/README.md#flag-histograms
for more information.

Bug: 1012578
Change-Id: Idf5aacf0aae6b6c2e5f4bdad621d028710e26052
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2026916
Commit-Queue: Rachel Carpenter <carpenterr@google.com>
Reviewed-by: dstockwell <dstockwell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#736264}

chrome/browser/about_flags.cc

@@ -4781,6 +4781,9 @@ const FeatureEntry kFeatureEntries[] = {
     {"split-settings-sync", flag_descriptions::kSplitSettingsSyncName,
      flag_descriptions::kSplitSettingsSyncDescription, kOsCrOS,
      FEATURE_VALUE_TYPE(chromeos::features::kSplitSettingsSync)},
+    {"help-app", flag_descriptions::kHelpAppName,
+     flag_descriptions::kHelpAppDescription, kOsCrOS,
+     FEATURE_VALUE_TYPE(chromeos::features::kHelpAppV2)},
     {"media-app", flag_descriptions::kMediaAppName,
      flag_descriptions::kMediaAppDescription, kOsCrOS,
      FEATURE_VALUE_TYPE(chromeos::features::kMediaApp)},

chrome/browser/flag-metadata.json

@@ -2404,6 +2404,11 @@
     "owners": [ "johnidel", "jkarlin" ],
     "expiry_milestone": 82
   },
+  {
+    "name": "help-app",
+    "owners": [ "//chromeos/components/help_app_ui/OWNERS" ],
+    "expiry_milestone": 90
+  },
   {
     "name": "homepage-settings-ui-conversion",
     "owners": [ "wenyufu", "chrome-android-app@chromium.org" ],

chrome/browser/flag_descriptions.cc

@@ -3422,6 +3422,10 @@ const char kGaiaActionButtonsName[] =
 const char kGaiaActionButtonsDescription[] =
     "Enable primary/secondary action button on Gaia login screen.";
 
+extern const char kHelpAppName[] = "Help App";
+extern const char kHelpAppDescription[] =
+    "Enables the chrome://help-app System Web App (SWA)";
+
 const char kHideArcMediaNotificationsName[] = "Hide ARC media notifications";
 const char kHideArcMediaNotificationsDescription[] =
     "Hides media notifications for ARC apps. Requires "

chrome/browser/flag_descriptions.h

@@ -1988,6 +1988,9 @@ extern const char kFuzzyAppSearchDescription[];
 extern const char kGaiaActionButtonsName[];
 extern const char kGaiaActionButtonsDescription[];
 
+extern const char kHelpAppName[];
+extern const char kHelpAppDescription[];
+
 extern const char kHideArcMediaNotificationsName[];
 extern const char kHideArcMediaNotificationsDescription[];
 

tools/metrics/histograms/enums.xml

@@ -37866,6 +37866,7 @@ from previous Chrome versions.
   <int value="-457174225" label="Av1Decoder:enabled"/>
   <int value="-456321929" label="ForceEnableSystemAec:disabled"/>
   <int value="-455203267" label="use_new_features_summary"/>
+  <int value="-454362199" label="HelpAppV2:disabled"/>
   <int value="-450976085"
       label="AutofillSaveCreditCardUsesImprovedMessaging:disabled"/>
   <int value="-449465495" label="disable-browser-task-scheduler"/>
@@ -39563,6 +39564,7 @@ from previous Chrome versions.
   <int value="1689123607" label="enable-app-link"/>
   <int value="1689183477" label="enable-merge-key-char-events"/>
   <int value="1689275095" label="InterestFeedFeedback:disabled"/>
+  <int value="1690248203" label="HelpAppV2:enabled"/>
   <int value="1690837904" label="save-previous-document-resources"/>
   <int value="1691568199" label="AndroidSpellCheckerNonLowEnd:disabled"/>
   <int value="1693094211" label="FilesNG:disabled"/>