Unknown process in Battery usage screen

Question

Recently I found this unknown process (shown without process name) is consuming substantial amount of my phone battery but couldn't identify what process it is. Can anyone throw me some light?

Phone model: LG G4

Android version: Android 6.0 (Marshmallow stock ROM)

^{Summary & Details (click images for larger variants)}

I've tried @Izzy suggestion and here are some useful information from adb shell dumpsys batterystats:-

Estimated power use (mAh):
    Capacity: 3000, Computed drain: 598, actual drain: 1560-1590
    Unaccounted: 962 ( )
    Screen: 250
    Uid u0a80: 185 ( cpu=185 wifi=0.0612 )
    Uid u0i4: 72.7 ( cpu=72.7 )
    Uid 0: 39.4 ( cpu=39.4 wifi=0.00828 )
    Uid 1000: 19.2 ( cpu=18.4 wake=0.101 wifi=0.519 sensor=0.159 )
    Idle: 8.58
...
...
...
u0a80:
    Wi-Fi network: 588.83MB received, 24.68MB sent (packets 472809 received, 334341 sent)
    Wake lock *net_scheduler* realtime
    Wake lock *alarm* realtime
    Wake lock AudioMix realtime
    Wake lock *launch* realtime
    Wake lock Icing realtime
    Wake lock WindowManager: 28m 50s 822ms full (55 times) realtime
    TOTAL wake: 28m 50s 822ms full realtime
    Foreground activities: 2h 15m 20s 943ms realtime (6 times)
    Foreground for: 4h 1m 48s 378ms
    Active for: 4h 1m 49s 192ms
    Running for: 4h 1m 57s 92ms
    Total cpu time: u=1h 26m 41s 960ms s=23m 19s 760ms p=0mAh
    Proc com.android.chrome:sandboxed_process7:
      CPU: 0ms usr + 0ms krn ; 0ms fg
      1 starts
    Proc com.android.chrome:sandboxed_process6:
      CPU: 0ms usr + 0ms krn ; 0ms fg
      1 starts
    Proc com.android.chrome:sandboxed_process5:
      CPU: 0ms usr + 0ms krn ; 0ms fg
      1 starts
    Proc com.android.chrome:sandboxed_process4:
      CPU: 0ms usr + 0ms krn ; 0ms fg
      1 starts
    Proc com.android.chrome:sandboxed_process3:
      CPU: 0ms usr + 0ms krn ; 0ms fg
      1 starts
    Proc com.android.chrome:sandboxed_process2:
      CPU: 45m 52s 890ms usr + 6m 9s 660ms krn ; 0ms fg
      1 starts
    Proc com.android.chrome:sandboxed_process1:
      CPU: 0ms usr + 0ms krn ; 0ms fg
      2 starts
    Proc com.android.chrome:sandboxed_process0:
      CPU: 0ms usr + 0ms krn ; 0ms fg
      2 starts
    Proc com.android.chrome:
      CPU: 23m 8s 490ms usr + 8m 20s 200ms krn ; 32m 9s 600ms fg
      3 starts
    Proc com.android.chrome:privileged_process0:
      CPU: 16m 21s 230ms usr + 8m 4s 380ms krn ; 0ms fg
      2 starts
    Apk com.android.chrome:
      Service org.chromium.chrome.browser.crash.MinidumpUploadService:
        Created for: 16ms uptime
        Starts: 2, launches: 2
      Service org.chromium.chrome.browser.download.DownloadNotificationService:
        Created for: 2h 0m 1s 303ms uptime
        Starts: 2, launches: 1
      Service org.chromium.chrome.browser.omaha.OmahaClient:
        Created for: 551ms uptime
        Starts: 5, launches: 5
      Service org.chromium.chrome.browser.media.ui.MediaNotificationManager$PlaybackListenerService:
        Created for: 8m 56s 795ms uptime
        Starts: 18, launches: 18
      Service org.chromium.content.app.PrivilegedProcessService0:
        Created for: 0ms uptime
        Starts: 0, launches: 2
      Service org.chromium.content.app.SandboxedProcessService7:
        Created for: 0ms uptime
        Starts: 0, launches: 1
      Service org.chromium.content.app.SandboxedProcessService6:
        Created for: 0ms uptime
        Starts: 0, launches: 1
      Service org.chromium.content.app.SandboxedProcessService5:
        Created for: 0ms uptime
        Starts: 0, launches: 1
      Service org.chromium.content.app.SandboxedProcessService4:
        Created for: 0ms uptime
        Starts: 0, launches: 1
      Service org.chromium.content.app.SandboxedProcessService3:
        Created for: 0ms uptime
        Starts: 0, launches: 1
      Service org.chromium.content.app.SandboxedProcessService2:
        Created for: 0ms uptime
        Starts: 0, launches: 1
      Service org.chromium.content.app.SandboxedProcessService1:
        Created for: 0ms uptime
        Starts: 0, launches: 1
      Service org.chromium.content.app.SandboxedProcessService0:
        Created for: 0ms uptime
        Starts: 0, launches: 2
      Service org.chromium.chrome.browser.ChromeBackgroundService:
        Created for: 433ms uptime
        Starts: 1, launches: 1
      Service org.chromium.chrome.browser.incognito.IncognitoNotificationService:
        Created for: 130ms uptime
        Starts: 1, launches: 1
  u0i0:
    Total cpu time: u=100ms s=80ms p=0mAh
    (nothing executed)
  u0i1:
    Total cpu time: u=50ms s=60ms p=0mAh
    (nothing executed)
  u0i2:
    Total cpu time: u=190ms s=30ms p=0mAh
    (nothing executed)
  u0i3:
    Total cpu time: u=120ms s=30ms p=0mAh
    (nothing executed)
  u0i4:
    Total cpu time: u=46m 30s 700ms s=6m 27s 600ms p=0mAh
    (nothing executed)
...
...