Remove event_parameter_name_

This CL removed |event_parameter_name_| from V8LazyEventListener.
|event_parameter_name_| is initialized on creating V8LazyEventListener,
but it does not have to be used because what the arguments should be
named is defined in standard.

Bug: 872138
Cq-Include-Trybots: luci.chromium.try:linux_layout_tests_slimming_paint_v2;master.tryserver.blink:linux_trusty_blink_rel
Change-Id: Id8dadeca9d5a8f0d3bb7232e80af298433ed01dd
Reviewed-on: https://chromium-review.googlesource.com/1219429
Commit-Queue: Yuki Yamada <yukiy@google.com>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Hitoshi Yoshida <peria@chromium.org>
Reviewed-by: Yuki Shiino <yukishiino@chromium.org>
Cr-Commit-Position: refs/heads/master@{#590909}
13 files changed