Implement basic USB device enumeration on Android.

device/usb/android/java/src/org/chromium/device/usb/ChromeUsbService.java

Index: device/usb/android/java/src/org/chromium/device/usb/ChromeUsbService.java
diff --git a/device/usb/android/java/src/org/chromium/device/usb/ChromeUsbService.java b/device/usb/android/java/src/org/chromium/device/usb/ChromeUsbService.java
new file mode 100644
index 0000000000000000000000000000000000000000..834ddb189764ae726e0d98329b6a9de81fe006a6
--- /dev/null
+++ b/device/usb/android/java/src/org/chromium/device/usb/ChromeUsbService.java
@@ -0,0 +1,45 @@
+// 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.device.usb;
+
+import android.content.Context;
+import android.hardware.usb.UsbDevice;
+import android.hardware.usb.UsbManager;
+
+import org.chromium.base.Log;
+import org.chromium.base.annotations.CalledByNative;
+import org.chromium.base.annotations.JNINamespace;
+
+import java.util.HashMap;
+
+/**
+ * Exposes android.hardware.usb.UsbManager as necessary for C++
+ * device::UsbServiceAndroid.
+ *
+ * Lifetime is controlled by device::UsbServiceAndroid.
+ */
+@JNINamespace("device")
+final class ChromeUsbService {
+    private static final String TAG = "Usb";
+
+    Context mContext;
+
+    private ChromeUsbService(Context context) {
+        mContext = context;
+        Log.v(TAG, "ChromeUsbService created.");
+    }
+
+    @CalledByNative
+    private static ChromeUsbService create(Context context) {
+        return new ChromeUsbService(context);
+    }
+
+    @CalledByNative
+    private Object[] getDevices() {
+        UsbManager manager = (UsbManager) mContext.getSystemService(Context.USB_SERVICE);
+        HashMap<String, UsbDevice> deviceList = manager.getDeviceList();
+        return deviceList.values().toArray();
+    }
+}