Fix crash on Linux caused by null deref

chrome/browser/ui/views/autofill/card_unmask_prompt_views.cc

Index: chrome/browser/ui/views/autofill/card_unmask_prompt_views.cc
diff --git a/chrome/browser/ui/views/autofill/card_unmask_prompt_views.cc b/chrome/browser/ui/views/autofill/card_unmask_prompt_views.cc
index 984aee66bb8e0baedd77ba19a06c8ab75e6b09b4..20425fb1b1dbba0a4cec53b2f44b501190bace80 100644
--- a/chrome/browser/ui/views/autofill/card_unmask_prompt_views.cc
+++ b/chrome/browser/ui/views/autofill/card_unmask_prompt_views.cc
@@ -109,7 +109,8 @@ void CardUnmaskPromptViews::GotVerificationResult(
     // TODO(estade): it's somewhat jarring when the error comes back too
     // quickly.
     overlay_animation_.Reset();
-    storage_row_->SetAlpha(255);
+    if (storage_row_)
+      storage_row_->SetAlpha(255);
     progress_overlay_->SetVisible(false);
 
     if (allow_retry) {