Auto merge of #22355 - gterzian:add_linux_sampler, r=asajeffrey,gterzian

Add linux sampler

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etc/taskcluster/docker/build.dockerfile

@@ -33,6 +33,9 @@ RUN \
         libglu1-mesa-dev \
         libbz2-dev \
         #
+        # sampling profiler
+        libunwind-dev \
+        #
         #
     && \
     #