Expand code that syncs ToS-seen prefs on Android.

chrome/android/java/src/org/chromium/chrome/browser/firstrun/FirstRunGlueImpl.java

Index: chrome/android/java/src/org/chromium/chrome/browser/firstrun/FirstRunGlueImpl.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/firstrun/FirstRunGlueImpl.java b/chrome/android/java/src/org/chromium/chrome/browser/firstrun/FirstRunGlueImpl.java
index 3a7f7add7cc0c8fd87e23776efb2e081d3027977..c0eab35b6dd149f2c9f612ffc3b34e353d53a582 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/firstrun/FirstRunGlueImpl.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/firstrun/FirstRunGlueImpl.java
@@ -24,15 +24,28 @@ public class FirstRunGlueImpl implements FirstRunGlue {
     private static final String CACHED_TOS_ACCEPTED_PREF = "first_run_tos_accepted";
 
     /**
-     * Synchronizes first run native and Java preferences. Previous versions would
-     * set only the native pref so this function synchronizes that state to Java.
+     * Synchronizes first run native and Java preferences.
      * Must be called after native initialization.
      */
     public static void cacheFirstRunPrefs() {
         SharedPreferences javaPrefs = ContextUtils.getAppSharedPreferences();
-        if (!javaPrefs.getBoolean(CACHED_TOS_ACCEPTED_PREF, false)
-                && PrefServiceBridge.getInstance().isFirstRunEulaAccepted()) {
-            javaPrefs.edit().putBoolean(CACHED_TOS_ACCEPTED_PREF, true).apply();
+        PrefServiceBridge prefsBridge = PrefServiceBridge.getInstance();
+        // Set both Java and native prefs if any of the three indicators indicate ToS has been
+        // accepted. This needed because:
+        //   - Old versions only set native pref, so this syncs Java pref.
+        //   - Backup & restore does not restore native pref, so this needs to update it.

[aberent, 2017/01/13 10:34:46]

Why not simply add the native pref to the list of backed up prefs (see
chrome_backup_agent.cc)?

+        //   - checkAnyUserHasSeenToS() may be true which needs to sync its state to the prefs.
+        boolean javaPrefValue = javaPrefs.getBoolean(CACHED_TOS_ACCEPTED_PREF, false);
+        boolean nativePrefValue = prefsBridge.isFirstRunEulaAccepted();
+        boolean userHasSeenTos =
+                ToSAckedReceiver.checkAnyUserHasSeenToS(ContextUtils.getApplicationContext());
+        if (javaPrefValue || nativePrefValue || userHasSeenTos) {
+            if (!javaPrefValue) {
+                javaPrefs.edit().putBoolean(CACHED_TOS_ACCEPTED_PREF, true).apply();
+            }
+            if (!nativePrefValue) {
+                prefsBridge.setEulaAccepted();
+            }
         }
     }