Add file category BackgroundTracingConfigImpl::CategoryPreset::BENCHMARK_RENDERERS

This category is chosen because it was found to be relevant to investigation of
an ongoing bug.

Bug: 1017889
Change-Id: I674a72bdf07529df33535149e57529c4bf9e0a4b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1959611Reviewed-by: oysteine <oysteine@chromium.org>
Commit-Queue: Oliver Li <olivierli@chromium.org>
Cr-Commit-Position: refs/heads/master@{#723429}

content/browser/tracing/background_tracing_config_impl.cc

@@ -510,7 +510,7 @@ TraceConfig BackgroundTracingConfigImpl::GetConfigForCategoryPreset(
       return TraceConfig(
           "benchmark,toplevel,ipc,base,ui,v8,renderer,blink,blink_gc,mojom,"
           "latency,latencyInfo,renderer_host,cc,memory,dwrite,fonts,browser,"
-          "ServiceWorker,disabled-by-default-v8.gc,"
+          "ServiceWorker,disabled-by-default-v8.gc,disabled-by-default-file"
           "disabled-by-default-blink_gc,disabled-by-default-lifecycles,"
           "disabled-by-default-renderer.scheduler,"
           "disabled-by-default-system_stats,disabled-by-default-cpu_profiler",