Warn web developer on missing favicon for PaymentRequest UI.

chrome/android/java/src/org/chromium/chrome/browser/payments/PaymentRequestImpl.java

Index: chrome/android/java/src/org/chromium/chrome/browser/payments/PaymentRequestImpl.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/payments/PaymentRequestImpl.java b/chrome/android/java/src/org/chromium/chrome/browser/payments/PaymentRequestImpl.java
index 6c78fa4cf750fec6802d214b05bec19454241756..e2f9f58bd0021fc231f1147341a69b113ba26e18 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/payments/PaymentRequestImpl.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/payments/PaymentRequestImpl.java
@@ -527,6 +527,7 @@ public class PaymentRequestImpl implements PaymentRequest, PaymentRequestUI.Clie
                 new FaviconHelper.FaviconImageCallback() {
                     @Override
                     public void onFaviconAvailable(Bitmap bitmap, String iconUrl) {
+                        if (bitmap == null) mClient.warnNoFavicon();

[gogerald1, 2017/05/08 22:13:56]

if(bitmap == null && mClient != null) mClient.warnNoFavicon();

This is inside an asynchronous call back,

[please use gerrit instead, 2017/05/09 15:23:05]

Done.

                         if (mUI != null && bitmap != null) mUI.setTitleBitmap(bitmap);
                         faviconHelper.destroy();
                     }