Note that as part of this change, the Device Service should register Gamepad JNI rather than //content/app.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/7550995f305f7407c8a67dc7715473fdc2e9c1ae

commit 7550995f305f7407c8a67dc7715473fdc2e9c1ae
Author: Matt Reynolds <mattreynolds@google.com>
Date: Wed May 23 03:12:55 2018

Remove pepper's parallel gamepad struct definitions

Before gamepad was partially servicified, gamepad struct definitions
resided in WebKit. These definitions must be identical for all readers
and writers to the shared memory buffer for consistency. Since pepper
may not depend on WebKit, the structs were duplicated in the pepper
gamepad client.

Now these structs have been moved out of WebKit and can be shared with
other components by depending on the target
//device/gamepad/public/cpp:shared_with_blink. This CL removes the
duplicate pepper definitions and switches all usages to the //device
definitions.

BUG=694998

Change-Id: I4cf596f5cff18f6dc8945a422a3cc9f70711c10c
Reviewed-on: https://chromium-review.googlesource.com/1062600
Reviewed-by: Bill Budge <bbudge@chromium.org>
Reviewed-by: Reilly Grant <reillyg@chromium.org>
Commit-Queue: Matt Reynolds <mattreynolds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#560914}
[modify] https://crrev.com/7550995f305f7407c8a67dc7715473fdc2e9c1ae/content/browser/renderer_host/pepper/pepper_gamepad_host.cc
[modify] https://crrev.com/7550995f305f7407c8a67dc7715473fdc2e9c1ae/content/browser/renderer_host/pepper/pepper_gamepad_host_unittest.cc
[modify] https://crrev.com/7550995f305f7407c8a67dc7715473fdc2e9c1ae/ppapi/proxy/BUILD.gn
[modify] https://crrev.com/7550995f305f7407c8a67dc7715473fdc2e9c1ae/ppapi/proxy/DEPS
[modify] https://crrev.com/7550995f305f7407c8a67dc7715473fdc2e9c1ae/ppapi/proxy/gamepad_resource.cc
[modify] https://crrev.com/7550995f305f7407c8a67dc7715473fdc2e9c1ae/ppapi/proxy/gamepad_resource.h
[modify] https://crrev.com/7550995f305f7407c8a67dc7715473fdc2e9c1ae/ppapi/shared_impl/ppb_gamepad_shared.cc
[modify] https://crrev.com/7550995f305f7407c8a67dc7715473fdc2e9c1ae/ppapi/shared_impl/ppb_gamepad_shared.h