Add connectivity check for Android feedback.

chrome/android/java/src/org/chromium/chrome/browser/feedback/ConnectivityChecker.java

Index: chrome/android/java/src/org/chromium/chrome/browser/feedback/ConnectivityChecker.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/feedback/ConnectivityChecker.java b/chrome/android/java/src/org/chromium/chrome/browser/feedback/ConnectivityChecker.java
new file mode 100644
index 0000000000000000000000000000000000000000..4c370f847e7d93a16e7d6c5a10e0cd33b0b5bbcb
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/feedback/ConnectivityChecker.java
@@ -0,0 +1,66 @@
+// Copyright 2015 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.feedback;
+
+import org.chromium.base.CalledByNative;
+import org.chromium.base.JNINamespace;
+import org.chromium.base.ThreadUtils;
+import org.chromium.base.VisibleForTesting;
+import org.chromium.chrome.browser.profiles.Profile;
+
+/**
+ * A utility class for checking if the device is currently connected to the Internet.
+ */
+@JNINamespace("chrome::android")
+public final class ConnectivityChecker {
+    private static final String DEFAULT_NO_CONTENT_URL = "http://clients4.google.com/generate_204";
+
+    /**
+     * A callback for whether the device is currently connected to the Internet.
+     */
+    public interface ConnectivityCheckerCallback {
+        /**
+         * Called when the result of the connectivity check is ready.
+         */
+        void onResult(boolean connected);
+    }
+
+    /**
+     * Starts an asynchronous request for checking whether the device is currently connected to the
+     * Internet. The result passed to the callback denotes whether the attempt to connect to the
+     * server was successful.
+     *
+     * If the profile or URL is invalid, the callback will be called with false.
+     * The server reply for the URL must respond with HTTP 204 without any redirects for the
+     * connectivity check to be successful.
+     *
+     * This method takes ownership of the callback object until the callback has happened.
+     * This method must be called on the main thread.
+     * @param profile the context to do the check in.
+     * @param timeoutMs number of milliseconds to wait before giving up waiting for a connection.
+     * @param callback the callback which will get the result.
+     */
+    public static void checkConnectivity(
+            Profile profile, long timeoutMs, ConnectivityCheckerCallback callback) {
+        checkConnectivity(profile, DEFAULT_NO_CONTENT_URL, timeoutMs, callback);
+    }
+
+    @VisibleForTesting
+    static void checkConnectivity(
+            Profile profile, String url, long timeoutMs, ConnectivityCheckerCallback callback) {
+        ThreadUtils.assertOnUiThread();
+        nativeCheckConnectivity(profile, url, timeoutMs, callback);
+    }
+
+    @CalledByNative
+    private static void executeCallback(Object callback, boolean connected) {
+        ((ConnectivityCheckerCallback) callback).onResult(connected);
+    }
+
+    private ConnectivityChecker() {}
+
+    private static native void nativeCheckConnectivity(
+            Profile profile, String url, long timeoutMs, ConnectivityCheckerCallback callback);
+}