Bug 1766646 - Vendor libwebrtc from 2d1a937ed2

Upstream commit: https://webrtc.googlesource.com/src/+/2d1a937ed2eca92e57746332bd4915caf0e29408
    [Merge M103] Add RTC_EXPORT to CurrentTaskQueueSetter

    This allows for its use in test targets in Chromium Windows, which fixes
    the compiled errors found in https://chromium-review.googlesource.com/c/chromium/src/+/3649679

    (cherry picked from commit 5b8dc1dbad3cbc333d131de4b1e3a9e1f22ca3a1)

    Change-Id: I738b2eaab8eca73c40e847ede67ff5e7757ec512
    Bug: chromium:1331333
    Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/262811
    Reviewed-by: Tomas Gunnarsson <tommi@webrtc.org>
    Commit-Queue: Tomas Gunnarsson <tommi@webrtc.org>
    Cr-Original-Commit-Position: refs/heads/main@{#36939}
    Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/264981
    Commit-Queue: Evan Shrubsole <eshr@webrtc.org>
    Cr-Commit-Position: refs/branch-heads/5060@{#2}
    Cr-Branched-From: 1389c76d9c79839a2ca069df1db48aa3f2e6a1ac-refs/heads/main@{#36868}

third_party/libwebrtc/README.mozilla

@@ -9444,3 +9444,5 @@ libwebrtc updated from /home/mfroman/git-checkouts/trial-webrtc-builds/moz-libwe
 libwebrtc updated from /home/mfroman/git-checkouts/trial-webrtc-builds/moz-libwebrtc-checkout/src commit mjfdev on 2022-07-15T06:16:29.672661.
 # python3 vendor-libwebrtc.py --from-local /home/mfroman/git-checkouts/trial-webrtc-builds/moz-libwebrtc-checkout/src --commit mjfdev libwebrtc
 libwebrtc updated from /home/mfroman/git-checkouts/trial-webrtc-builds/moz-libwebrtc-checkout/src commit mjfdev on 2022-07-15T06:23:03.336226.
+# python3 vendor-libwebrtc.py --from-local /home/mfroman/git-checkouts/trial-webrtc-builds/moz-libwebrtc-checkout/src --commit mjfdev libwebrtc
+libwebrtc updated from /home/mfroman/git-checkouts/trial-webrtc-builds/moz-libwebrtc-checkout/src commit mjfdev on 2022-07-15T06:28:57.435629.

third_party/libwebrtc/api/task_queue/task_queue_base.h

@@ -130,7 +130,7 @@ class RTC_LOCKABLE RTC_EXPORT TaskQueueBase {
   bool IsCurrent() const { return Current() == this; }
 
  protected:
-  class CurrentTaskQueueSetter {
+  class RTC_EXPORT CurrentTaskQueueSetter {
    public:
     explicit CurrentTaskQueueSetter(TaskQueueBase* task_queue);
     CurrentTaskQueueSetter(const CurrentTaskQueueSetter&) = delete;