[bfcache] Remove passing NavigationControllerTest.* tests from filter.

The following tests now pass with BackForwardCacheEnabled:
NavigationControllerTest.Back_NewPending
NavigationControllerTest.CopyStateFromAndPruneSourcePending

Bug: 1003744
Change-Id: Ib2803487eba3612e2f00918854284e2e5b9ddb63
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1810521Reviewed-by: Arthur Sonzogni <arthursonzogni@chromium.org>
Commit-Queue: Lowell Manners <lowell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#697559}

testing/buildbot/filters/bfcache.content_unittests.filter

@@ -4,12 +4,6 @@
 # the BackForwardCache.
 -FrameServiceBaseTest.DidFinishNavigation
 
-# During WebContent destructor, in RenderFrameHost:
-# Check failed: !is_active().
-# https://crbug.com/1003744
--NavigationControllerTest.Back_NewPending
--NavigationControllerTest.CopyStateFromAndPruneSourcePending
-
 # Expects the process used by the previous document to exit.
 -RenderFrameHostManagerTest.DeleteFrameAfterSwapOutACK