Specify the use of RiskAdvisoryData for Wallet unmask requests on iOS.

See https://codereview.chromium.org/1058473002/ for background.

BUG=484806

Review URL: https://codereview.chromium.org/1148123003

Cr-Commit-Position: refs/heads/master@{#330885}

components/autofill/core/browser/card_unmask_delegate.cc

@@ -7,7 +7,16 @@
 namespace autofill {
 
 CardUnmaskDelegate::UnmaskResponse::UnmaskResponse()
-    : should_store_pan(false) {}
+    : should_store_pan(false),
+      providing_risk_advisory_data(false) {
+#if defined(OS_IOS)
+  // On iOS, we generate a RiskAdvisoryData instead of the
+  // BrowserNativeFingerprinting produced on other platforms. This field
+  // directs the Wallet client to configure the request accordingly.
+  providing_risk_advisory_data = true;
+#endif
+}
+
 CardUnmaskDelegate::UnmaskResponse::~UnmaskResponse() {}
 
 }  // namespace autofill

components/autofill/core/browser/card_unmask_delegate.h

@@ -34,7 +34,7 @@ class CardUnmaskDelegate {
 
     // Whether we're providing the alternative "risk advisory data" in risk_data
     // (as opposed to the normal browser fingerprint).
-    bool providing_risk_advisory_data = false;
+    bool providing_risk_advisory_data;
   };
 
   // Called when the user has attempted a verification. Prompt is still