The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2d3ac961d2ae9ff01eba996a8c63d7ce18556445

commit 2d3ac961d2ae9ff01eba996a8c63d7ce18556445
Author: rtoy <rtoy@chromium.org>
Date: Mon Nov 07 23:04:14 2016

Remove ZeroPole class and files

The ZeroPole class is not used anywhere and therefore not tested.
Remove it.

BUG= 657033 
TEST=compile still works

Review-Url: https://codereview.chromium.org/2432473002
Cr-Commit-Position: refs/heads/master@{#430406}

[modify] https://crrev.com/2d3ac961d2ae9ff01eba996a8c63d7ce18556445/third_party/WebKit/Source/platform/BUILD.gn
[modify] https://crrev.com/2d3ac961d2ae9ff01eba996a8c63d7ce18556445/third_party/WebKit/Source/platform/audio/DynamicsCompressor.h
[delete] https://crrev.com/d9c107f9476d72220f6ab128578183ba9f1b18f6/third_party/WebKit/Source/platform/audio/ZeroPole.cpp
[delete] https://crrev.com/d9c107f9476d72220f6ab128578183ba9f1b18f6/third_party/WebKit/Source/platform/audio/ZeroPole.h