Add the compositor and memory categories to slow reports

This adds compositor trace events to the BENCHMARK_RENDERERS slow reports,
which is needed to analyze certain events related to frame timing.

Change-Id: Iae65efa506b20a7cdee088c6c379d4e3b049b676
Reviewed-on: https://chromium-review.googlesource.com/c/1446507
Commit-Queue: Etienne Bergeron <etienneb@chromium.org>
Reviewed-by: Etienne Bergeron <etienneb@chromium.org>
Reviewed-by: oysteine <oysteine@chromium.org>
Cr-Commit-Position: refs/heads/master@{#629168}

content/browser/tracing/background_tracing_manager_impl.cc

@@ -738,7 +738,7 @@ TraceConfig BackgroundTracingManagerImpl::GetConfigForCategoryPreset(
     case BackgroundTracingConfigImpl::CategoryPreset::BENCHMARK_RENDERERS:
       return TraceConfig(
           "benchmark,toplevel,ipc,base,ui,v8,renderer,blink,blink_gc,mojom,"
-          "latency,latencyInfo,renderer_host,"
+          "latency,latencyInfo,renderer_host,cc,memory,"
           "disabled-by-default-v8.gc,"
           "disabled-by-default-blink_gc,"
           "disabled-by-default-renderer.scheduler,"