Settings (and general) restore fixes

Pro tem, we ignore wifi configuration data when restoring system settings.
This is not ideal, but it *does* mean we do not bounce wifi off and on
again during the extended restore process, which in turn means we don't
interfere with things like the Play Store's download of applications.
We do continue to back up wifi configuration, and will start using that
data again when the new implementation that restores AP configurations
without having to bounce wifi comes to pass.

Also, this CL fixes a longstanding bug in BackupDataInput.skipEntityData()
that was being reproduced reliably once settings restore was skipping
the wifi-related entities in the restore stream.

Bug 7249405

Change-Id: I61520a9a116b66ebdf95734d09d9afd46406df01

Author: Christopher Tate

libs/androidfw/BackupData.cpp

@@ -327,6 +327,7 @@ BackupDataReader::SkipEntityData()
         if (pos == -1) {
             return errno;
         }
+        m_pos = pos;
     }
     SKIP_PADDING();
     return NO_ERROR;

packages/SettingsProvider/src/com/android/providers/settings/SettingsBackupAgent.java

@@ -61,6 +61,12 @@ public class SettingsBackupAgent extends BackupAgentHelper {
     private static final boolean DEBUG = false;
     private static final boolean DEBUG_BACKUP = DEBUG || false;
 
+    /* Don't restore wifi config until we have new logic for parsing the
+     * saved wifi config and configuring the new APs without having to
+     * disable and re-enable wifi
+     */
+    private static final boolean NAIVE_WIFI_RESTORE = false;
+
     private static final String KEY_SYSTEM = "system";
     private static final String KEY_SECURE = "secure";
     private static final String KEY_GLOBAL = "global";
@@ -307,7 +313,7 @@ public void onRestore(BackupDataInput data, int appVersionCode,
                 mSettingsHelper.applyAudioSettings();
             } else if (KEY_SECURE.equals(key)) {
                 restoreSettings(data, Settings.Secure.CONTENT_URI, movedToGlobal);
-            } else if (KEY_WIFI_SUPPLICANT.equals(key)) {
+            } else if (NAIVE_WIFI_RESTORE && KEY_WIFI_SUPPLICANT.equals(key)) {
                 int retainedWifiState = enableWifi(false);
                 restoreWifiSupplicant(FILE_WIFI_SUPPLICANT, data);
                 FileUtils.setPermissions(FILE_WIFI_SUPPLICANT,
@@ -321,7 +327,7 @@ public void onRestore(BackupDataInput data, int appVersionCode,
                 byte[] localeData = new byte[size];
                 data.readEntityData(localeData, 0, size);
                 mSettingsHelper.setLocaleData(localeData, size);
-            } else if (KEY_WIFI_CONFIG.equals(key)) {
+            } else if (NAIVE_WIFI_RESTORE && KEY_WIFI_CONFIG.equals(key)) {
                 restoreFileData(mWifiConfigFile, data);
              } else {
                 data.skipEntityData();