Fix extensions policy browser tests with network service.

Bug: 871549
Cq-Include-Trybots: luci.chromium.try:linux_mojo
Change-Id: I53fe4c0163964961e1a44fa9f81b95e63c395433
Reviewed-on: https://chromium-review.googlesource.com/1167989Reviewed-by: Doug Turner <dougt@chromium.org>
Commit-Queue: John Abd-El-Malek <jam@chromium.org>
Cr-Commit-Position: refs/heads/master@{#582024}

chrome/test/data/extensions/good2_update_manifest.xml

@@ -5,7 +5,7 @@
 -->
 <gupdate xmlns='http://www.google.com/update2/response' protocol='2.0'>
   <app appid='ldnnhddmnhbkjipkidpdiheffobcpfmf'>
-    <updatecheck codebase='http://mock.http/extensions/good2.crx'
+    <updatecheck codebase='http://update.extension/extensions/good2.crx'
                  version='1.0.0.1' />
    </app>
 </gupdate>

chrome/test/data/extensions/good_v1_update_manifest.xml

@@ -5,7 +5,7 @@
 -->
 <gupdate xmlns='http://www.google.com/update2/response' protocol='2.0'>
   <app appid='ldnnhddmnhbkjipkidpdiheffobcpfmf'>
-    <updatecheck codebase='http://mock.http/extensions/good_v1.crx'
+    <updatecheck codebase='http://update.extension/extensions/good_v1.crx'
                  version='1.0.0.0' />
    </app>
 </gupdate>

testing/buildbot/filters/mojo.fyi.network_browser_tests.filter

@@ -16,16 +16,6 @@
 -SubresourceFilterBrowserTest.FailedProvisionalLoadInMainframe
 -WebViewTest.WebViewInBackgroundPage
 
-# These tests uses net::URLRequestFilter (through TestRequestInterceptor) to
-# mock out network responses, and use ExtensionDownloader to issue requests,
-# which has yet to be switched from URLFetcher.
-# https://crbug.com/844928
--PolicyTest.ExtensionInstallForcelist
--PolicyTest.ExtensionInstallForcelist_DefaultedUpdateUrl
--PolicyTest.ExtensionMinimumVersionForceInstalled
--PolicyTest.ExtensionMinimumVersionRequired
--PolicyTest.ExtensionMinimumVersionRequiredAlt
--PolicyTest.ExtensionRecommendedInstallationMode
 
 # These tests uses net::URLRequestFilter (through TestRequestInterceptor) to
 # mock out network responses, and use URLFetcherDownloader to issue requests,