GitLab

This is a reland of 583f52a3

See https://chromium-review.googlesource.com/c/chromium/src/+/2585991/2
for underlying MSAN issue unrelated to this CL (just caught by this
CL's tests)

Original change's description:
> Search Prefetch Streaming requests can be cancelled after headers
>
> The goal of this CL is to allow unneeded requests to be cancelled
> when they are unlikely to be navigated to. This is achieved through
> a few avenues of change:
>
> -- When the user navigates to something in omnibox, the URL is reported
> to Search Prefetch Service to be able to mark it as likely to be served
> (using kCanBeServedAndUserClicked when the request is kCanBeServed).
> This occurs before the omnibox is closed and all results are wiped.
> -- kCanBeServed are wiped when omnibox closes.
> -- Streaming requests will no longer pause the mojo channel, so they can
> witness the Complete event to be able to make the request as complete.
> -- As part of above, we store the response body in memory instead of
> just handing off the data pipe. Data pipes have a 500k data limit, which
> search requests typically go over. Net won't send the complete event
> until all data is in the pipe. Therefore we store the data and create a
> pipe to navigation if needed.
> -- Full body implementation now reports kComplete where it used to
> report kCanBeServed.
>
> Bug: 1156325
> Change-Id: Ied70a3eafd896801e263f631cb4d80556e762180
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2583112
> Reviewed-by: Tarun Bansal <tbansal@chromium.org>
> Reviewed-by: Robert Ogden <robertogden@chromium.org>
> Commit-Queue: Ryan Sturm <ryansturm@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#835897}

Bug: 1156325
Change-Id: Ifeeed421e9124f99a0f6aa27ca08734a1b130878
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2587263Reviewed-by: Robert Ogden <robertogden@chromium.org>
Reviewed-by: Tarun Bansal <tbansal@chromium.org>
Commit-Queue: Ryan Sturm <ryansturm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#836212}