Keep browser process alive while there are platform apps with background pages running.

chrome/browser/extensions/api/usb/usb_apitest.cc

 // Copyright (c) 2012 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.
 
 #include "chrome/browser/extensions/api/usb/usb_api.h"
 #include "chrome/browser/extensions/extension_apitest.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/usb/usb_service.h"
 #include "chrome/browser/usb/usb_service_factory.h"
 #include "chrome/common/chrome_switches.h"
@@ skipping 63 matching lines @@
   }
 
  protected:
   scoped_refptr<MockUsbDevice> mock_device_;
 };
 
 }  // namespace
 
 IN_PROC_BROWSER_TEST_F(UsbApiTest, DeviceHandling) {
   EXPECT_CALL(*mock_device_, Close(_)).Times(1);
-  ASSERT_TRUE(RunExtensionTest("usb/device_handling"));
+  ASSERT_TRUE(RunPlatformAppTest("usb/device_handling"));
 }
 
 IN_PROC_BROWSER_TEST_F(UsbApiTest, TransferEvent) {
   EXPECT_CALL(*mock_device_,
       ControlTransfer(UsbDevice::OUTBOUND, UsbDevice::STANDARD,
           UsbDevice::DEVICE, 1, 2, 3, _, 1, _, _))
       .WillOnce(InvokeUsbTransferCallback<9>(USB_TRANSFER_COMPLETED));
   EXPECT_CALL(*mock_device_,
       BulkTransfer(UsbDevice::OUTBOUND, 1, _, 1, _, _))
       .WillOnce(InvokeUsbTransferCallback<5>(USB_TRANSFER_COMPLETED));
   EXPECT_CALL(*mock_device_,
       InterruptTransfer(UsbDevice::OUTBOUND, 2, _, 1, _, _))
       .WillOnce(InvokeUsbTransferCallback<5>(USB_TRANSFER_COMPLETED));
   EXPECT_CALL(*mock_device_,
       IsochronousTransfer(UsbDevice::OUTBOUND, 3, _, 1, 1, 1, _, _))
       .WillOnce(InvokeUsbTransferCallback<7>(USB_TRANSFER_COMPLETED));
   EXPECT_CALL(*mock_device_, Close(_)).Times(AnyNumber());
-  ASSERT_TRUE(RunExtensionTest("usb/transfer_event"));
+  ASSERT_TRUE(RunPlatformAppTest("usb/transfer_event"));
 }
 
 IN_PROC_BROWSER_TEST_F(UsbApiTest, ZeroLengthTransfer) {
   EXPECT_CALL(*mock_device_, BulkTransfer(_, _, _, 0, _, _))
       .WillOnce(InvokeUsbTransferCallback<5>(USB_TRANSFER_COMPLETED));
   EXPECT_CALL(*mock_device_, Close(_)).Times(AnyNumber());
-  ASSERT_TRUE(RunExtensionTest("usb/zero_length_transfer"));
+  ASSERT_TRUE(RunPlatformAppTest("usb/zero_length_transfer"));
 }
 
 IN_PROC_BROWSER_TEST_F(UsbApiTest, TransferFailure) {
   EXPECT_CALL(*mock_device_, BulkTransfer(_, _, _, _, _, _))
       .WillOnce(InvokeUsbTransferCallback<5>(USB_TRANSFER_COMPLETED))
       .WillOnce(InvokeUsbTransferCallback<5>(USB_TRANSFER_ERROR))
       .WillOnce(InvokeUsbTransferCallback<5>(USB_TRANSFER_TIMEOUT));
   EXPECT_CALL(*mock_device_, Close(_)).Times(AnyNumber());
-  ASSERT_TRUE(RunExtensionTest("usb/transfer_failure"));
+  ASSERT_TRUE(RunPlatformAppTest("usb/transfer_failure"));
 }