Pad HID output reports on Windows to the maximum output report size.

extensions/browser/api/hid/hid_apitest.cc

 // Copyright 2014 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 "base/bind.h"
 #include "base/run_loop.h"
 #include "base/thread_task_runner_handle.h"
 #include "device/hid/hid_collection_info.h"
 #include "device/hid/hid_connection.h"
 #include "device/hid/hid_device_info.h"
@@ skipping 40 matching lines @@
     scoped_refptr<IOBuffer> buffer(new IOBuffer(sizeof(kResult)));
     buffer->data()[0] = report_id;
     memcpy(buffer->data() + 1, kResult, sizeof(kResult) - 1);
     ThreadTaskRunnerHandle::Get()->PostTask(
         FROM_HERE, base::Bind(callback, true, buffer, sizeof(kResult)));
   }
 
   void PlatformWrite(scoped_refptr<net::IOBuffer> buffer,
                      size_t size,
                      const WriteCallback& callback) override {
-    const char kExpected[] = "This is a HID output report.";
+    const char kExpected[] = "o-report";  // 8 bytes
     bool result = false;
     if (size == sizeof(kExpected)) {
       uint8_t report_id = buffer->data()[0];
       uint8_t expected_report_id = device_info()->has_report_id() ? 1 : 0;
       if (report_id == expected_report_id) {
         if (memcmp(buffer->data() + 1, kExpected, sizeof(kExpected) - 1) == 0) {
           result = true;
         }
       }
     }
@@ skipping 135 matching lines @@
   // Device C was not returned by chrome.hid.getDevices, the app will not get
   // a notification.
   hid_service_->RemoveDevice("C");
   // Device A was returned, the app will get a notification.
   hid_service_->RemoveDevice("A");
   ASSERT_TRUE(result_listener.WaitUntilSatisfied());
   EXPECT_EQ("success", result_listener.message());
 }
 
 }  // namespace extensions