Reland "Added support of getting coverage on mac"

This is a reland of 207cfdfbd8896e093f7088123eb729df174614d3
This was not a cause of bug chromium:888061

Original change's description:
> Added support of getting coverage on mac
>
> Bug: chromium:844647
> Change-Id: Ia358d3a1dfc9a53149d68f811652f38245a0b408
> Reviewed-on: https://webrtc-review.googlesource.com/101041
> Reviewed-by: Patrik Höglund <phoglund@webrtc.org>
> Commit-Queue: Artem Titarenko <artit@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#24779}

Bug: chromium:844647
Change-Id: I14ecd48f2c6e5cf4978110b6aefae02222d3ff1e
Reviewed-on: https://webrtc-review.googlesource.com/101780
Reviewed-by: Artem Titarenko <artit@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#24817}
diff --git a/sdk/BUILD.gn b/sdk/BUILD.gn
index 36909e2..a50b93d 100644
--- a/sdk/BUILD.gn
+++ b/sdk/BUILD.gn
@@ -43,6 +43,10 @@
       "-Wstrict-overflow",
       "-Wmissing-field-initializers",
     ]
+
+    if (use_clang_coverage) {
+      configs = [ "//build/config/coverage:default_coverage" ]
+    }
   }
 
   config("used_from_extension") {