Remove double initialization of the TracingSamplerProfiler

These calls were already being done in ChromeMainDelegate::BasicStartupComplete()
resulting in the Renderer/GPU main threads to be sampled twice.

R=avi@chromium.org

Bug: 1067416
Change-Id: I5e7f57989fde11224c905f092483185ab5be54e8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2154402Reviewed-by: Avi Drissman <avi@chromium.org>
Commit-Queue: oysteine <oysteine@chromium.org>
Cr-Commit-Position: refs/heads/master@{#761114}

content/gpu/gpu_main.cc

@@ -46,7 +46,6 @@
 #include "gpu/ipc/service/gpu_init.h"
 #include "gpu/ipc/service/gpu_watchdog_thread.h"
 #include "media/gpu/buildflags.h"
-#include "services/tracing/public/cpp/stack_sampling/tracing_sampler_profiler.h"
 #include "services/tracing/public/cpp/trace_startup.h"
 #include "third_party/angle/src/gpu_info_util/SystemInfo.h"
 #include "ui/events/platform/platform_event_source.h"
@@ -389,10 +388,6 @@ int GpuMain(const MainFunctionParams& parameters) {
     tracing::EnableStartupTracingIfNeeded();
 #endif  // OS_POSIX && !OS_ANDROID && !!OS_MACOSX
 
-  // Setup tracing sampler profiler as early as possible.
-  std::unique_ptr<tracing::TracingSamplerProfiler> tracing_sampler_profiler =
-      tracing::TracingSamplerProfiler::CreateOnMainThread();
-
 #if defined(OS_MACOSX)
   // A GPUEjectPolicy of 'wait' is set in the Info.plist of the browser
   // process, meaning it is "responsible" for making sure it and its

content/renderer/renderer_main.cc

@@ -36,7 +36,6 @@
 #include "mojo/public/cpp/bindings/mojo_buildflags.h"
 #include "ppapi/buildflags/buildflags.h"
 #include "services/service_manager/sandbox/switches.h"
-#include "services/tracing/public/cpp/stack_sampling/tracing_sampler_profiler.h"
 #include "services/tracing/public/cpp/trace_startup.h"
 #include "third_party/blink/public/platform/scheduler/web_thread_scheduler.h"
 #include "third_party/webrtc_overrides/init_webrtc.h"  // nogncheck
@@ -211,10 +210,6 @@ int RendererMain(const MainFunctionParams& parameters) {
     }
 #endif  // OS_POSIX && !OS_ANDROID && !!OS_MACOSX
 
-    // Setup tracing sampler profiler as early as possible.
-    auto tracing_sampler_profiler =
-        tracing::TracingSamplerProfiler::CreateOnMainThread();
-
     if (need_sandbox)
       should_run_loop = platform.EnableSandbox();