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

extensions/browser/api/hid/hid_apitest.cc

Index: extensions/browser/api/hid/hid_apitest.cc
diff --git a/extensions/browser/api/hid/hid_apitest.cc b/extensions/browser/api/hid/hid_apitest.cc
index c29c42195ecfcf6eee516c67359922c0e1e3d375..63012a10663c01d282df1dd9b4fa00678bc371e5 100644
--- a/extensions/browser/api/hid/hid_apitest.cc
+++ b/extensions/browser/api/hid/hid_apitest.cc
@@ -58,7 +58,7 @@ class MockHidConnection : public HidConnection {
   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];