docker stats CPU above 100%

Description
docker stats CPU shows values above 100%.

Steps to reproduce the issue:

1. run docker stats while a container is using high cpu

Describe the results you received:
CPU column shows values above 100% (110%, 250%...)

Describe the results you expected:
CPU column values should be normalized to 100%. Conceptually, header CPU % means max 100%.

Additional information you deem important (e.g. issue happens only occasionally):

Output of docker version:

Client: Docker Engine - Community
 Version:           19.03.2
 API version:       1.40
 Go version:        go1.12.8
 Git commit:        6a30dfc
 Built:             Thu Aug 29 05:26:49 2019
 OS/Arch:           windows/amd64
 Experimental:      false

Server: Docker Engine - Community
 Engine:
  Version:          19.03.2
  API version:      1.40 (minimum version 1.12)
  Go version:       go1.12.8
  Git commit:       6a30dfc
  Built:            Thu Aug 29 05:32:21 2019
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          v1.2.6
  GitCommit:        894b81a4b802e4eb2a91d1ce216b8817763c29fb
 runc:
  Version:          1.0.0-rc8
  GitCommit:        425e105d5a03fabd737a126ad93d62a9eeede87f
 docker-init:
  Version:          0.18.0
  GitCommit:        fec3683

Output of docker info:

Client:
 Debug Mode: false

Server:
 Containers: 11
  Running: 11
  Paused: 0
  Stopped: 0
 Images: 251
 Server Version: 19.03.2
 Storage Driver: overlay2
  Backing Filesystem: extfs
  Supports d_type: true
  Native Overlay Diff: true
 Logging Driver: json-file
 Cgroup Driver: cgroupfs
 Plugins:
  Volume: local
  Network: bridge host ipvlan macvlan null overlay
  Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
 Swarm: inactive
 Runtimes: runc
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: 894b81a4b802e4eb2a91d1ce216b8817763c29fb
 runc version: 425e105d5a03fabd737a126ad93d62a9eeede87f
 init version: fec3683
 Security Options:
  seccomp
   Profile: default
 Kernel Version: 4.9.184-linuxkit
 Operating System: Docker Desktop
 OSType: linux
 Architecture: x86_64
 CPUs: 4
 Total Memory: 3.837GiB
 Name: docker-desktop
 ID: PL7Z:37ZA:FGN5:EBPE:KYFT:HSFI:YXJP:2MOK:ESB3:MML3:6G22:7ZIK
 Docker Root Dir: /var/lib/docker
 Debug Mode: true
  File Descriptors: 143
  Goroutines: 152
  System Time: 2019-10-11T20:46:04.5961211Z
  EventsListeners: 4
 Registry: https://index.docker.io/v1/
 Labels:
 Experimental: false
 Insecure Registries:
  127.0.0.0/8
 Live Restore Enabled: false
 Product License: Community Engine

Additional environment details (AWS, VirtualBox, physical, etc.):
Using 4 core CPU.

Start by reproducing the issue with docker stats while a container uses high CPU, using the four-CPU environment described in the report. Trace the docker stats CPU display and determine how the value should be normalized; done means the CPU column no longer exceeds 100% while existing stats behavior remains intact.