Revert "RtpTransceiverInterface: introduce SetOfferedRtpHeaderExtensions."

This reverts commit 71db9acc4019b8c9c13b14e6a022cbb3b4255b09.

Reason for revert: breaks downstream project.
Reason for force push: win bot broken.

Original change's description:
> RtpTransceiverInterface: introduce SetOfferedRtpHeaderExtensions.
>
> This change adds exposure of a new transceiver method for
> modifying the extensions offered in the next SDP negotiation,
> following spec details in https://w3c.github.io/webrtc-extensions/#rtcrtptransceiver-interface.
>
> Features:
> - The interface allows to control the negotiated direction as
>   per https://tools.ietf.org/html/rfc5285#page-7.
> - The interface allows to remove an extension from SDP
>   negotiation by modifying the direction to
>   RtpTransceiverDirection::kStopped.
>
> Note: support for signalling directionality of header extensions
> in the SDP isn't implemented yet.
>
> https://chromestatus.com/feature/5680189201711104.
> Intent to prototype: https://groups.google.com/a/chromium.org/g/blink-dev/c/65YdUi02yZk
>
> Bug: chromium:1051821
> Change-Id: Iaabc34446f038c46d93c442e90c2a77f77d542d4
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/176408
> Reviewed-by: Harald Alvestrand <hta@webrtc.org>
> Commit-Queue: Markus Handell <handellm@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#31487}

TBR=hta@webrtc.org,handellm@webrtc.org

# Not skipping CQ checks because original CL landed > 1 day ago.

No-Try: true
Bug: chromium:1051821
Change-Id: I70e1a07225d7eeec7480fa5577d8ff647eba6902
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/177103
Commit-Queue: Markus Handell <handellm@webrtc.org>
Reviewed-by: Markus Handell <handellm@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31516}
diff --git a/pc/rtp_transceiver_unittest.cc b/pc/rtp_transceiver_unittest.cc
index e3f05c4..5e34573 100644
--- a/pc/rtp_transceiver_unittest.cc
+++ b/pc/rtp_transceiver_unittest.cc
@@ -25,7 +25,6 @@
 using ::testing::Eq;
 using ::testing::Field;
 using ::testing::Not;
-using ::testing::Property;
 using ::testing::Return;
 using ::testing::ReturnRef;
 
@@ -79,95 +78,27 @@
   EXPECT_EQ(nullptr, transceiver.channel());
 }
 
-class RtpTransceiverTestForHeaderExtensions : public ::testing::Test {
- public:
-  RtpTransceiverTestForHeaderExtensions()
-      : channel_manager_(std::make_unique<cricket::FakeMediaEngine>(),
-                         std::make_unique<cricket::FakeDataEngine>(),
-                         rtc::Thread::Current(),
-                         rtc::Thread::Current()),
-        extensions_(
-            {RtpHeaderExtensionCapability("uri1",
-                                          1,
-                                          RtpTransceiverDirection::kSendOnly),
-             RtpHeaderExtensionCapability("uri2",
-                                          2,
-                                          RtpTransceiverDirection::kRecvOnly),
-             RtpHeaderExtensionCapability(RtpExtension::kMidUri,
-                                          3,
-                                          RtpTransceiverDirection::kSendRecv),
-             RtpHeaderExtensionCapability(RtpExtension::kVideoRotationUri,
-                                          4,
-                                          RtpTransceiverDirection::kSendRecv)}),
-        transceiver_(RtpSenderProxyWithInternal<RtpSenderInternal>::Create(
-                         rtc::Thread::Current(),
-                         new rtc::RefCountedObject<MockRtpSenderInternal>()),
-                     RtpReceiverProxyWithInternal<RtpReceiverInternal>::Create(
-                         rtc::Thread::Current(),
-                         new rtc::RefCountedObject<MockRtpReceiverInternal>()),
-                     &channel_manager_,
-                     extensions_) {}
-
-  cricket::ChannelManager channel_manager_;
-  std::vector<RtpHeaderExtensionCapability> extensions_;
-  RtpTransceiver transceiver_;
-};
-
-TEST_F(RtpTransceiverTestForHeaderExtensions, OffersChannelManagerList) {
-  EXPECT_EQ(transceiver_.HeaderExtensionsToOffer(), extensions_);
-}
-
-TEST_F(RtpTransceiverTestForHeaderExtensions, ModifiesDirection) {
-  auto modified_extensions = extensions_;
-  modified_extensions[0].direction = RtpTransceiverDirection::kSendOnly;
-  EXPECT_TRUE(
-      transceiver_.SetOfferedRtpHeaderExtensions(modified_extensions).ok());
-  EXPECT_EQ(transceiver_.HeaderExtensionsToOffer(), modified_extensions);
-  modified_extensions[0].direction = RtpTransceiverDirection::kRecvOnly;
-  EXPECT_TRUE(
-      transceiver_.SetOfferedRtpHeaderExtensions(modified_extensions).ok());
-  EXPECT_EQ(transceiver_.HeaderExtensionsToOffer(), modified_extensions);
-  modified_extensions[0].direction = RtpTransceiverDirection::kSendRecv;
-  EXPECT_TRUE(
-      transceiver_.SetOfferedRtpHeaderExtensions(modified_extensions).ok());
-  EXPECT_EQ(transceiver_.HeaderExtensionsToOffer(), modified_extensions);
-  modified_extensions[0].direction = RtpTransceiverDirection::kInactive;
-  EXPECT_TRUE(
-      transceiver_.SetOfferedRtpHeaderExtensions(modified_extensions).ok());
-  EXPECT_EQ(transceiver_.HeaderExtensionsToOffer(), modified_extensions);
-}
-
-TEST_F(RtpTransceiverTestForHeaderExtensions, AcceptsStoppedExtension) {
-  auto modified_extensions = extensions_;
-  modified_extensions[0].direction = RtpTransceiverDirection::kStopped;
-  EXPECT_TRUE(
-      transceiver_.SetOfferedRtpHeaderExtensions(modified_extensions).ok());
-  EXPECT_EQ(transceiver_.HeaderExtensionsToOffer(), modified_extensions);
-}
-
-TEST_F(RtpTransceiverTestForHeaderExtensions, RejectsUnsupportedExtension) {
-  std::vector<RtpHeaderExtensionCapability> modified_extensions(
-      {RtpHeaderExtensionCapability("uri3", 1,
-                                    RtpTransceiverDirection::kSendRecv)});
-  EXPECT_THAT(transceiver_.SetOfferedRtpHeaderExtensions(modified_extensions),
-              Property(&RTCError::type, RTCErrorType::INVALID_PARAMETER));
-  EXPECT_EQ(transceiver_.HeaderExtensionsToOffer(), extensions_);
-}
-
-TEST_F(RtpTransceiverTestForHeaderExtensions,
-       RejectsStoppedMandatoryExtensions) {
-  std::vector<RtpHeaderExtensionCapability> modified_extensions = extensions_;
-  // Attempting to stop the mandatory MID extension.
-  modified_extensions[2].direction = RtpTransceiverDirection::kStopped;
-  EXPECT_THAT(transceiver_.SetOfferedRtpHeaderExtensions(modified_extensions),
-              Property(&RTCError::type, RTCErrorType::INVALID_MODIFICATION));
-  EXPECT_EQ(transceiver_.HeaderExtensionsToOffer(), extensions_);
-  modified_extensions = extensions_;
-  // Attempting to stop the mandatory video orientation extension.
-  modified_extensions[3].direction = RtpTransceiverDirection::kStopped;
-  EXPECT_THAT(transceiver_.SetOfferedRtpHeaderExtensions(modified_extensions),
-              Property(&RTCError::type, RTCErrorType::INVALID_MODIFICATION));
-  EXPECT_EQ(transceiver_.HeaderExtensionsToOffer(), extensions_);
+TEST(RtpTransceiverTest,
+     InitsWithChannelManagerRtpHeaderExtensionCapabilities) {
+  cricket::ChannelManager channel_manager(
+      std::make_unique<cricket::FakeMediaEngine>(),
+      std::make_unique<cricket::FakeDataEngine>(), rtc::Thread::Current(),
+      rtc::Thread::Current());
+  std::vector<RtpHeaderExtensionCapability> extensions({
+      RtpHeaderExtensionCapability("uri1", 1,
+                                   RtpTransceiverDirection::kSendRecv),
+      RtpHeaderExtensionCapability("uri2", 2,
+                                   RtpTransceiverDirection::kRecvOnly),
+  });
+  RtpTransceiver transceiver(
+      RtpSenderProxyWithInternal<RtpSenderInternal>::Create(
+          rtc::Thread::Current(),
+          new rtc::RefCountedObject<MockRtpSenderInternal>()),
+      RtpReceiverProxyWithInternal<RtpReceiverInternal>::Create(
+          rtc::Thread::Current(),
+          new rtc::RefCountedObject<MockRtpReceiverInternal>()),
+      &channel_manager, extensions);
+  EXPECT_EQ(transceiver.HeaderExtensionsToOffer(), extensions);
 }
 
 }  // namespace webrtc