Remove unnecessary check in IsSystemRealTimeMessage.

Remove unnecessary check in IsSystemRealTimeMessage.

The 'data <= 0xff' check in IsSystemRealTimeMessage is unnecessary as
|data| is a uint8 integer. This CL removes the check to prevent the
following compilation error when building with '-Werror=type-limits'.

../../media/midi/midi_message_queue.cc: In function 'bool
media::{anonymous}::IsSystemRealTimeMessage(uint8)':
../../media/midi/midi_message_queue.cc:27:34: error: comparison is
always true due to limited range of data type [-Werror=type-limits]
   return 0xf8 <= data && data <= 0xff;
                                  ^

BUG=424334, 427726
TEST=Build successfully with '-Werror=type-limits' using the GN flow.

Committed: https://crrev.com/4454938c07fd3d03112d0faae956f2fe47fc58be
Cr-Commit-Position: refs/heads/master@{#301803}

[Ben Chan, 2014-10-29 00:06:03]

benchan@chromium.org changed reviewers:
+ yukawa@chromium.org

[Ben Chan, 2014-10-29 00:08:46]

benchan@chromium.org changed reviewers:
+ toyoshim@chromium.org, yhirano@chromium.org

[yhirano, 2014-10-29 01:40:34]

lgtm

[Ben Chan, 2014-10-29 06:31:56]

The CQ bit was checked by benchan@chromium.org

[commit-bot: I haz the power, 2014-10-29 06:32:57]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/683693003/1

[commit-bot: I haz the power, 2014-10-29 07:24:29]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-10-29 07:25:07]

Patchset 1 (id:??) landed as
https://crrev.com/4454938c07fd3d03112d0faae956f2fe47fc58be
Cr-Commit-Position: refs/heads/master@{#301803}