[bfcache] Unfilter blink web_tests

After enabling H264 which run WPT,the failing blink web_tests
should be working with BackForwardCache enabled.

Bug: 1103214
Change-Id: I5059bf682f0aa441fd9d5a8237e90057213796d7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2395236Reviewed-by: Harald Alvestrand <hta@chromium.org>
Commit-Queue: Sreeja Kamishetty <sreejakshetty@chromium.org>
Cr-Commit-Position: refs/heads/master@{#804939}

third_party/blink/web_tests/FlagExpectations/enable-features=BackForwardCache

 # tags: [ Android Fuchsia Linux Mac Mac10.12 Mac10.13 Win Win7 Win10 ]
 # tags: [ Release Debug ]
 # results: [ Timeout Crash Pass Failure Slow Skip ]
-
-# Tests that fail with BackForwardCache, running on linux-bfcache-debug bot.
-crbug.com/1010870 virtual/gpu/fast/canvas/color-space/canvas-createImageBitmap-e_srgb.html [ Failure ]
-crbug.com/1010870 virtual/gpu/fast/canvas/canvas-composite-alpha.html [ Failure ]
-crbug.com/1010870 virtual/gpu/fast/canvas/canvas-composite-text-alpha.html [ Failure ]
-crbug.com/1103214 virtual/webrtc-wpt-plan-b/external/wpt/webrtc/simulcast/h264.https.html [ Failure ]
-crbug.com/1103214 external/wpt/webrtc/protocol/video-codecs.https.html [ Failure ]
-crbug.com/1103214 virtual/webrtc-wpt-plan-b/external/wpt/webrtc/protocol/video-codecs.https.html [ Failure ]
-crbug.com/1103214 external/wpt/webrtc/simulcast/h264.https.html [ Failure ]