Revert of [Android] Migrate javascript settings to a content setting from a pref.

chrome/android/java/src/org/chromium/chrome/browser/preferences/PrefServiceBridge.java

Index: chrome/android/java/src/org/chromium/chrome/browser/preferences/PrefServiceBridge.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/preferences/PrefServiceBridge.java b/chrome/android/java/src/org/chromium/chrome/browser/preferences/PrefServiceBridge.java
index d2332b48a8c42ea4b7df49b9763cbf8e0f4729a5..c3005e17b81555db9ea8ccf8dd3c2f87c4c983e8 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/preferences/PrefServiceBridge.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/preferences/PrefServiceBridge.java
@@ -4,11 +4,7 @@
 
 package org.chromium.chrome.browser.preferences;
 
-import android.content.Context;
-import android.content.SharedPreferences;
-import android.preference.PreferenceManager;
 import android.text.TextUtils;
-import android.util.Log;
 
 import org.chromium.base.CalledByNative;
 import org.chromium.base.ThreadUtils;
@@ -35,9 +31,6 @@
     public static final int SUPERVISED_USER_FILTERING_WARN = 1;
     public static final int SUPERVISED_USER_FILTERING_BLOCK = 2;
 
-    private static final String MIGRATION_PREF_KEY = "PrefMigrationVersion";
-    private static final int MIGRATION_CURRENT_VERSION = 1;
-
     private static String sProfilePath;
 
     // Object to notify when "clear browsing data" completes.
@@ -147,25 +140,6 @@
      */
     public static boolean isInitialized() {
         return sInstance != null;
-    }
-
-    /**
-     * Migrates (synchronously) the preferences to the most recent version.
-     */
-    public void migratePreferences(Context context) {
-        SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(context);
-        int currentVersion = preferences.getInt(MIGRATION_PREF_KEY, 0);
-        if (currentVersion == MIGRATION_CURRENT_VERSION) return;
-        if (currentVersion > MIGRATION_CURRENT_VERSION) {
-            Log.e(LOG_TAG, "Saved preferences version is newer than supported.  Attempting to "
-                    + "run an older version of Chrome without clearing data is unsupported and "
-                    + "the results may be unpredictable.");
-        }
-
-        if (currentVersion <= 0) {
-            nativeMigrateJavascriptPreference();
-        }
-        preferences.edit().putInt(MIGRATION_PREF_KEY, MIGRATION_CURRENT_VERSION).commit();
     }
 
     /**
@@ -772,7 +746,6 @@
     private native void nativeResetTranslateDefaults();
     private native boolean nativeGetJavaScriptEnabled();
     private native void nativeSetJavaScriptEnabled(boolean enabled);
-    private native void nativeMigrateJavascriptPreference();
     private native void nativeClearBrowsingData(boolean history, boolean cache,
             boolean cookiesAndSiteData, boolean passwords, boolean formData);
     private native void nativeSetAllowCookiesEnabled(boolean allow);