Don't toggle Data Saver again until it receives a callback.

BUG: 29253107
Change-Id: I4371f947086a45be6709d2a560d27d1f5f0e79c4

src/com/android/settings/datausage/DataSaverSummary.java

@@ -46,6 +46,9 @@ public class DataSaverSummary extends SettingsPreferenceFragment
     private AppStateDataUsageBridge mDataUsageBridge;
     private Session mSession;
 
+    // Flag used to avoid infinite loop due if user switch it on/off too quicky.
+    private boolean mSwitching;
+
     @Override
     public void onCreate(Bundle icicle) {
         super.onCreate(icicle);
@@ -87,8 +90,14 @@ public class DataSaverSummary extends SettingsPreferenceFragment
 
     @Override
     public void onSwitchChanged(Switch switchView, boolean isChecked) {
+        synchronized(this) {
+            if (mSwitching) {
+                return;
+            }
+            mSwitching = true;
             mDataSaverBackend.setDataSaverEnabled(isChecked);
         }
+    }
 
     @Override
     protected int getMetricsCategory() {
@@ -102,7 +111,10 @@ public class DataSaverSummary extends SettingsPreferenceFragment
 
     @Override
     public void onDataSaverChanged(boolean isDataSaving) {
+        synchronized(this) {
             mSwitchBar.setChecked(isDataSaving);
+            mSwitching = false;
+        }
     }
 
     @Override