The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/ec46f437c78de0a8d9eb003f15cce2855a6ff86b

commit ec46f437c78de0a8d9eb003f15cce2855a6ff86b
Author: Mugdha Lakhani <nator@chromium.org>
Date: Tue Sep 11 15:10:52 2018

[Background Fetch] Reject when requests have body.

With this CL,
1. Record the BackgroundFetch.HasRequestsWithBody UMA metric, which is
true if any requests in the background fetch contain a body, false otherwise.
2. Reject the fetch() promise, if any requests do contain a body.

Bug:  881344 
Change-Id: I595800adefe1dcc2c8bb04bec2295cc2886d963d
Reviewed-on: https://chromium-review.googlesource.com/1210125
Commit-Queue: Mugdha Lakhani <nator@chromium.org>
Reviewed-by: Peter Beverloo <peter@chromium.org>
Reviewed-by: Rayan Kanso <rayankans@chromium.org>
Reviewed-by: Steven Holte <holte@chromium.org>
Cr-Commit-Position: refs/heads/master@{#590309}
[modify] https://crrev.com/ec46f437c78de0a8d9eb003f15cce2855a6ff86b/third_party/WebKit/LayoutTests/external/wpt/background-fetch/fetch.https.window-expected.txt
[modify] https://crrev.com/ec46f437c78de0a8d9eb003f15cce2855a6ff86b/third_party/WebKit/LayoutTests/external/wpt/background-fetch/fetch.https.window.js
[modify] https://crrev.com/ec46f437c78de0a8d9eb003f15cce2855a6ff86b/third_party/blink/renderer/modules/background_fetch/background_fetch_manager.cc
[modify] https://crrev.com/ec46f437c78de0a8d9eb003f15cce2855a6ff86b/third_party/blink/renderer/modules/background_fetch/background_fetch_manager.h
[modify] https://crrev.com/ec46f437c78de0a8d9eb003f15cce2855a6ff86b/third_party/blink/renderer/modules/background_fetch/background_fetch_manager_test.cc
[modify] https://crrev.com/ec46f437c78de0a8d9eb003f15cce2855a6ff86b/tools/metrics/histograms/histograms.xml