Revert of GN: Refactor modules_unittests to eliminate package boundary violations. (patchset #4 id:130001 of https://codereview.webrtc.org/2649563002/ )

Reason for revert:
Did break the bots.
https://build.chromium.org/p/client.webrtc/builders/iOS32%20Release/builds/9807

Original issue's description:
> GN: Refactor modules_unittests to eliminate package boundary violations.
>
> Also move bwe_simulator to webrtc/modules/remote_bitrate_estimator
>
> BUG=webrtc:6954
> NOTRY=True
>
> Review-Url: https://codereview.webrtc.org/2649563002
> Cr-Commit-Position: refs/heads/master@{#16270}
> Committed: 36cb55d715

TBR=kjellander@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:6954

Review-Url: https://codereview.webrtc.org/2651023005
Cr-Commit-Position: refs/heads/master@{#16271}

webrtc/modules/video_coding/BUILD.gn

@@ -310,36 +310,6 @@ if (rtc_include_tests) {
       "../../test:test_support",
     ]
   }
-
-  rtc_source_set("video_coding_modules_tests") {
-    testonly = true
-    sources = [
-      "codecs/test/videoprocessor_integrationtest.cc",
-      "codecs/vp8/test/vp8_impl_unittest.cc",
-    ]
-    deps = [
-      ":video_codecs_test_framework",
-      ":video_coding",
-      ":webrtc_h264",
-      ":webrtc_vp8",
-      ":webrtc_vp9",
-      "../..:webrtc_common",
-      "../../api:video_frame_api",
-      "../../base:rtc_base_approved",
-      "../../common_video:common_video",
-      "../../media:rtc_media_base",
-      "../../test:test_support",
-      "../../test:video_test_common",
-    ]
-    if (rtc_use_h264) {
-      defines = [ "WEBRTC_VIDEOPROCESSOR_H264_TESTS" ]
-    }
-    if (!build_with_chromium && is_clang) {
-      # Suppress warnings from the Chromium Clang plugin (bugs.webrtc.org/163).
-      suppressed_configs += [ "//build/config/clang:find_bad_constructs" ]
-    }
-  }
-
   rtc_source_set("video_coding_unittests") {
     testonly = true
     sources = [