Cache ChromeStartupDelegate flags

Expose ChromeStartupDelegate feature flag to Java (missed in
https://crrev.com/c/2523359) and cache flag and variations so they can
be accessed before the native FeatureList is initialized.

Bug: 1143402
Change-Id: I1f624009e00bc6d40bbef39b6a093cb15a60c50a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2529701Reviewed-by: Theresa  <twellington@chromium.org>
Commit-Queue: Natalie Chouinard <chouinard@chromium.org>
Cr-Commit-Position: refs/heads/master@{#825965}

chrome/android/java/src/org/chromium/chrome/browser/app/flags/ChromeCachedFlags.java

@@ -13,6 +13,7 @@ import org.chromium.chrome.browser.firstrun.FirstRunUtils;
 import org.chromium.chrome.browser.flags.CachedFeatureFlags;
 import org.chromium.chrome.browser.flags.CachedFieldTrialParameter;
 import org.chromium.chrome.browser.flags.ChromeFeatureList;
+import org.chromium.chrome.browser.init.ChromeStartupDelegate;
 import org.chromium.chrome.browser.tasks.ConditionalTabStripUtils;
 import org.chromium.chrome.browser.tasks.ReturnToChromeExperimentsUtil;
 import org.chromium.chrome.browser.tasks.tab_management.TabUiFeatureUtilities;
@@ -50,6 +51,7 @@ public class ChromeCachedFlags {
         List<String> featuresToCache = Arrays.asList(
                 ChromeFeatureList.ANDROID_MANAGED_BY_MENU_ITEM,
                 ChromeFeatureList.ANDROID_PARTNER_CUSTOMIZATION_PHENOTYPE,
+                ChromeFeatureList.CHROME_STARTUP_DELEGATE,
                 ChromeFeatureList.CLOSE_TAB_SUGGESTIONS,
                 ChromeFeatureList.CRITICAL_PERSISTED_TAB_DATA,
                 ChromeFeatureList.COMMAND_LINE_ON_NON_ROOTED,
@@ -82,6 +84,7 @@ public class ChromeCachedFlags {
         List<CachedFieldTrialParameter> fieldTrialsToCache = Arrays.asList(
                 AppMenuPropertiesDelegateImpl.ACTION_BAR_VARIATION,
                 AppMenuPropertiesDelegateImpl.THREE_BUTTON_ACTION_BAR_VARIATION,
+                ChromeStartupDelegate.ENABLED,
                 ConditionalTabStripUtils.CONDITIONAL_TAB_STRIP_INFOBAR_LIMIT,
                 ConditionalTabStripUtils.CONDITIONAL_TAB_STRIP_INFOBAR_PERIOD,
                 ConditionalTabStripUtils.CONDITIONAL_TAB_STRIP_SESSION_TIME_MS,

chrome/android/java/src/org/chromium/chrome/browser/init/ChromeStartupDelegate.java

@@ -4,9 +4,17 @@
 
 package org.chromium.chrome.browser.init;
 
+import org.chromium.chrome.browser.flags.BooleanCachedFieldTrialParameter;
+import org.chromium.chrome.browser.flags.ChromeFeatureList;
+
 /**
  * Delegate for Chrome startup initialization, implemented downstream.
  */
 public class ChromeStartupDelegate {
+    public static final String ENABLED_PARAM = "enabled";
+    public static final BooleanCachedFieldTrialParameter ENABLED =
+            new BooleanCachedFieldTrialParameter(
+                    ChromeFeatureList.CHROME_STARTUP_DELEGATE, ENABLED_PARAM, false);
+
     public void init() {}
 }

chrome/browser/flags/android/chrome_feature_list.cc

@@ -138,6 +138,7 @@ const base::Feature* kFeaturesExposedToJava[] = {
     &kChromeShareScreenshot,
     &kChromeSharingHub,
     &kChromeSharingHubV15,
+    &kChromeStartupDelegate,
     &kCommandLineOnNonRooted,
     &kConditionalTabStripAndroid,
     &kContentSuggestionsScrollToLoad,

chrome/browser/flags/android/java/src/org/chromium/chrome/browser/flags/CachedFeatureFlags.java

@@ -49,6 +49,7 @@ public class CachedFeatureFlags {
         {
             put(ChromeFeatureList.ANDROID_MANAGED_BY_MENU_ITEM, true);
             put(ChromeFeatureList.ANDROID_PARTNER_CUSTOMIZATION_PHENOTYPE, true);
+            put(ChromeFeatureList.CHROME_STARTUP_DELEGATE, false);
             put(ChromeFeatureList.CONDITIONAL_TAB_STRIP_ANDROID, false);
             put(ChromeFeatureList.HORIZONTAL_TAB_SWITCHER_ANDROID, false);
             put(ChromeFeatureList.SERVICE_MANAGER_FOR_DOWNLOAD, true);