Revert "Only enable conference mode simulcast allocations with flag enabled"

This reverts commit 32ca95145c4636374266f5b5d4d1ac43658bc758.

Reason for revert: Internal test failure

Original change's description:
> Only enable conference mode simulcast allocations with flag enabled
> 
> Non-conference mode simulcast screenshares were mistakenly using the
> conference mode semantics in the simulcast rate allocator, which broke
> spec compliant usage in some situation.
> 
> This behavior should only be used when explicitly using the SDP entry
> "a=x-google-flag:conference" in both offer and answer.
> 
> Bug: webrtc:11310, chromium:1093819
> Change-Id: Ibcba75c88a8405d60467546b33977a782e04e469
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/179081
> Reviewed-by: Harald Alvestrand <hta@webrtc.org>
> Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
> Commit-Queue: Florent Castelli <orphis@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#31828}

TBR=ilnik@webrtc.org,hta@webrtc.org,orphis@webrtc.org

Change-Id: I5ccb6e87594f491ba09fe6b837ee24d63db878ca
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: webrtc:11310
Bug: chromium:1093819
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/180801
Reviewed-by: Florent Castelli <orphis@webrtc.org>
Commit-Queue: Florent Castelli <orphis@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31829}
diff --git a/modules/video_coding/video_codec_initializer_unittest.cc b/modules/video_coding/video_codec_initializer_unittest.cc
index 686396c..d5a18f0 100644
--- a/modules/video_coding/video_codec_initializer_unittest.cc
+++ b/modules/video_coding/video_codec_initializer_unittest.cc
@@ -42,8 +42,7 @@
 static const uint32_t kDefaultMaxBitrateBps = 2000000;
 static const uint32_t kDefaultMinTransmitBitrateBps = 400000;
 static const int kDefaultMaxQp = 48;
-static const uint32_t kScreenshareTl0BitrateBps = 120000;
-static const uint32_t kScreenshareConferenceTl0BitrateBps = 200000;
+static const uint32_t kScreenshareTl0BitrateBps = 200000;
 static const uint32_t kScreenshareCodecTargetBitrateBps = 200000;
 static const uint32_t kScreenshareDefaultFramerate = 5;
 // Bitrates for the temporal layers of the higher screenshare simulcast stream.
@@ -127,7 +126,7 @@
   VideoStream DefaultScreenshareStream() {
     VideoStream stream = DefaultStream();
     stream.min_bitrate_bps = 30000;
-    stream.target_bitrate_bps = kScreenshareCodecTargetBitrateBps;
+    stream.target_bitrate_bps = kScreenshareTl0BitrateBps;
     stream.max_bitrate_bps = 1000000;
     stream.max_framerate = kScreenshareDefaultFramerate;
     stream.num_temporal_layers = 2;
@@ -175,23 +174,6 @@
   EXPECT_EQ(0U, bitrate_allocation.get_sum_bps());
 }
 
-TEST_F(VideoCodecInitializerTest, TemporalLayeredVp8ScreenshareConference) {
-  SetUpFor(VideoCodecType::kVideoCodecVP8, 1, 2, true);
-  streams_.push_back(DefaultScreenshareStream());
-  EXPECT_TRUE(InitializeCodec());
-  bitrate_allocator_->SetLegacyConferenceMode(true);
-
-  EXPECT_EQ(1u, codec_out_.numberOfSimulcastStreams);
-  EXPECT_EQ(2u, codec_out_.VP8()->numberOfTemporalLayers);
-  VideoBitrateAllocation bitrate_allocation =
-      bitrate_allocator_->Allocate(VideoBitrateAllocationParameters(
-          kScreenshareCodecTargetBitrateBps, kScreenshareDefaultFramerate));
-  EXPECT_EQ(kScreenshareCodecTargetBitrateBps,
-            bitrate_allocation.get_sum_bps());
-  EXPECT_EQ(kScreenshareConferenceTl0BitrateBps,
-            bitrate_allocation.GetBitrate(0, 0));
-}
-
 TEST_F(VideoCodecInitializerTest, TemporalLayeredVp8Screenshare) {
   SetUpFor(VideoCodecType::kVideoCodecVP8, 1, 2, true);
   streams_.push_back(DefaultScreenshareStream());