Don't show the Data Saver promo in incognito mode

chrome/android/java/src/org/chromium/chrome/browser/preferences/datareduction/DataReductionPromoScreen.java

Index: chrome/android/java/src/org/chromium/chrome/browser/preferences/datareduction/DataReductionPromoScreen.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/preferences/datareduction/DataReductionPromoScreen.java b/chrome/android/java/src/org/chromium/chrome/browser/preferences/datareduction/DataReductionPromoScreen.java
index 514e2313ad84b08867c88ded6a3c26491be5cab5..1216b8fb90f16f76be705bec0db1cb7ebc657e73 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/preferences/datareduction/DataReductionPromoScreen.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/preferences/datareduction/DataReductionPromoScreen.java
@@ -24,10 +24,11 @@ public class DataReductionPromoScreen extends PromoDialog {
      * Launch the data reduction promo, if it needs to be displayed.
      * @return Whether the data reduction promo was displayed.
      */
-    public static boolean launchDataReductionPromo(Activity parentActivity) {
+    public static boolean launchDataReductionPromo(Activity parentActivity, boolean isIncognito) {
         // The promo is displayed if Chrome is launched directly (i.e., not with the intent to
         // navigate to and view a URL on startup), the instance is part of the field trial,
         // and the promo has not been displayed before.
+        if (isIncognito) return false;
         if (!DataReductionPromoUtils.canShowPromos()) return false;
         if (DataReductionPromoUtils.getDisplayedFreOrSecondRunPromo()) return false;
         // Showing the promo dialog in multiwindow mode is broken on Galaxy Note devices: