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This patch intends to fix a crash issue when GPUDevice is destroyed
before the destruction of any other WebGPU objects that are created
from it.

Without this patch, when a GPUDevice is destroyed its related
WebGPUSerializer is also destroyed immediately, which causes crash
when any other WebGPU object which belongs to this GPUDevice is
destroyed afterwards.

In this patch, we introduce DawnDeviceClientSerializerHolder to
manage the reference count of all the WebGPU objects that belong to
one device_client_id (relates to one WebGPUSerializer).
- When GPUDevice is created,
  scopted_ptr<DawnDeviceClientSerializerHolder> is also created with
  dawn_control_client and device_client_id.
- When other WebGPU objects are created from a GPUDevice, they will all
  get a reference of scopted_ptr<DawnDeviceClientSerializerHolder> from
  the GPUDevice
- The WebGPUSerializer will only be released in the destructor of
  scopted_ptr<DawnDeviceClientSerializerHolder> (that should be the
  time when the GPUDevice and all the WebGPU objects that are created
  from it are released).

Note that scoped_refptr<DawnControlClientHolder> is referenced twice in
GPUDevice and other WebGPU objects that are created from it as they are
still inherited from DawnObjectBase. We will fix this issue in the next
patch.

BUG=chromium:996713, chromium:1072833

Change-Id: Ibb83f9c906fa38f15712ba0f20c67e4929ba3c0e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2192672Reviewed-by: Austin Eng <enga@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Jiawei Shao <jiawei.shao@intel.com>
Cr-Commit-Position: refs/heads/master@{#768579}