Change USBTransferInResult.data to a DataView.

This modification is copied from Web Bluetooth where it was found to be
more ergonomic to provide a DataView as the default type for a buffer
value as it provides methods such as getUint8() by default.

BUG=492204

Review URL: https://codereview.chromium.org/1639503002

Cr-Commit-Position: refs/heads/master@{#371560}
2 files changed