mojo: Mark DataView readers as WARN_UNUSED_RESULT.

It's important to check this return value to make sure that
deserialization actually succeeded.

BUG=652129

Review-Url: https://codereview.chromium.org/2392713002
Cr-Commit-Position: refs/heads/master@{#422681}


CrOS-Libchrome-Original-Commit: 88622215affa898deaf1399711387289cd8ff8ed
3 files changed
tree: e52479155be3af858561c4fa6e5b6d72bedb2c68
  1. base/
  2. build/
  3. components/
  4. dbus/
  5. device/
  6. ipc/
  7. mojo/
  8. testing/
  9. third_party/
  10. ui/