media/track: Replace wtf/Assertions.h macros in favor of base/logging.h macros

Replaced wtf/Assertions.h macros in favor of base/logging.h
macros in core/html/track folder.

ASSERT, ASSERT_UNUSED -> DCHECK
ASSERT_NOT_REACHED -> NOTREACHED
ASSERT_WITH_SECURITY_IMPLICATION -> SECURITY_DCHECK

BUG=596522

Review-Url: https://codereview.chromium.org/2003543002
Cr-Commit-Position: refs/heads/master@{#395078}
21 files changed