Detect locally installed native Android payment apps.

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

Index: chrome/android/java/src/org/chromium/chrome/browser/payments/AndroidPaymentAppFactory.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/payments/AndroidPaymentAppFactory.java b/chrome/android/java/src/org/chromium/chrome/browser/payments/AndroidPaymentAppFactory.java
new file mode 100644
index 0000000000000000000000000000000000000000..74a3dcb379f3b4a6f2ba70586779c22ff7b7a127
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/payments/AndroidPaymentAppFactory.java
@@ -0,0 +1,71 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chrome.browser.payments;
+
+import android.content.Context;
+import android.content.Intent;
+import android.content.pm.PackageManager;
+import android.content.pm.ResolveInfo;
+import android.net.Uri;
+
+import org.chromium.chrome.browser.payments.PaymentAppFactory.PaymentAppCreatedCallback;
+import org.chromium.chrome.browser.payments.PaymentAppFactory.PaymentAppFactoryAddition;
+import org.chromium.content.browser.ContentViewCore;
+import org.chromium.content_public.browser.WebContents;
+import org.chromium.ui.base.WindowAndroid;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+/** Builds instances of payment apps based on installed third party Android payment apps. */
+public class AndroidPaymentAppFactory implements PaymentAppFactoryAddition {
+    private static final String PAY_INTENT_ACTION = "org.chromium.intent.action.PAY";
+    private static final String IS_READY_TO_PAY_INTENT_ACTION =

[gone, 2017/01/03 19:20:03]

Prefix ACTION instead of suffixing; that's how Intent.ACTION_* is standardized.

[please use gerrit instead, 2017/01/04 17:27:53]

Done.

+            "org.chromium.intent.action.IS_READY_TO_PAY";
+    private static final String METHOD_PREFIX = "https://";
+
+    @Override
+    public void create(Context context, WebContents webContents, Set<String> methods,
+            PaymentAppCreatedCallback callback) {
+        WindowAndroid window = ContentViewCore.fromWebContents(webContents).getWindowAndroid();

[gone, 2017/01/03 19:20:03]

1) getWindowAndroid can return null, which doesn't seem to be accounted for.

2) It's much safer to cache the WebContents instead of the WindowAndroid to deal
with tab reparenting (e.g.), which results in getWindowAndroid() being null.

[please use gerrit instead, 2017/01/04 17:27:53]

Checking getWindowAndroid() for null now. Thank you.

Can ContentViewCore.fromWebContents(webContents) return null?
Caching WebContents instead.

[gone, 2017/01/04 19:40:57]

Javadoc suggests so, yeah.  Should probably null check that where you moved it
to.

[please use gerrit instead, 2017/01/04 20:02:50]

Done.

+        Map<String, AndroidPaymentApp> installedApps = new HashMap<>();
+        PackageManager pm = context.getPackageManager();
+        Intent payIntent = new Intent(PAY_INTENT_ACTION);
+
+        for (String methodName : methods) {
+            if (!methodName.startsWith(METHOD_PREFIX)) continue;
+
+            payIntent.setData(Uri.parse(methodName));
+            List<ResolveInfo> matches = pm.queryIntentActivities(payIntent, 0);
+            for (int i = 0; i < matches.size(); i++) {
+                ResolveInfo match = matches.get(i);
+                String packageName = match.activityInfo.packageName;
+                AndroidPaymentApp installedApp = installedApps.get(packageName);
+                if (installedApp == null) {
+                    CharSequence label = match.loadLabel(pm);
+                    installedApp =
+                            new AndroidPaymentApp(window, packageName, match.activityInfo.name,
+                                    label == null ? "" : label.toString(), match.loadIcon(pm));
+                    callback.onPaymentAppCreated(installedApp);
+                    installedApps.put(packageName, installedApp);
+                }
+                installedApp.addMethodName(methodName);
+            }
+        }
+
+        List<ResolveInfo> matches =
+                pm.queryIntentServices(new Intent(IS_READY_TO_PAY_INTENT_ACTION), 0);
+        for (int i = 0; i < matches.size(); i++) {
+            ResolveInfo match = matches.get(i);
+            String packageName = match.serviceInfo.packageName;
+            AndroidPaymentApp installedApp = installedApps.get(packageName);
+            if (installedApp != null) installedApp.setIsReadyToPayService(match.serviceInfo.name);
+        }
+
+        callback.onAllPaymentAppsCreated();
+    }
+}