Reduce the size of local_frame_view.h

This CL reduces the pre-processed size of local_frame_view.h by 1.01MB.

* Change jank_tracker_ from an in-place data member to
  std::unique_ptr<>. This change reduces the size by 800KB+.


Bug: 242216
Cq-Include-Trybots: luci.chromium.try:linux_layout_tests_slimming_paint_v2;master.tryserver.blink:linux_trusty_blink_rel
Change-Id: I0aebabdde355fb071e3debe5cd628e929033727c
Reviewed-on: https://chromium-review.googlesource.com/1220867
Reviewed-by: Daniel Bratell <bratell@opera.com>
Commit-Queue: Kent Tamura <tkent@chromium.org>
Cr-Commit-Position: refs/heads/master@{#590625}
8 files changed