This reverts commit 65e27b1b.

Reason for revert:
Causes failures in the GPU FYI x64 bots and ANGLE CQ bots.

See for example 
https://build.chromium.org/p/chromium.gpu.fyi/builders/Win7%20x64%20Release%20%28NVIDIA%29/builds/12511

[1010/202058.449:FATAL:at_exit.cc(58)] Check failed: false. Tried to RegisterCallback without an AtExitManager
Backtrace:
	base::debug::StackTrace::StackTrace [0x000007FEEF138495+69]
	base::debug::StackTrace::StackTrace [0x000007FEEF112EC3+19]
	logging::LogMessage::~LogMessage [0x000007FEEF08BB3D+253]
	base::AtExitManager::RegisterTask [0x000007FEEF0FE469+105]
	base::AtExitManager::RegisterCallback [0x000007FEEF0FE3E2+258]
	base::trace_event::TraceEventETWExport::GetInstance [0x000007FEEF139EA0+112]
	base::trace_event::TraceEventETWExport::IsCategoryGroupEnabled [0x000007FEEF13A31D+125]
	base::trace_event::TraceLog::UpdateCategoryState [0x000007FEEF0A9333+371]
	base::trace_event::CategoryRegistry::GetOrCreateCategoryLocked [0x000007FEEF14105F+655]
	base::trace_event::TraceLog::GetCategoryGroupEnabled [0x000007FEEF0A7092+210]
	base::debug::TaskAnnotator::DidQueueTask [0x000007FEEF167705+53]
	base::internal::IncomingTaskQueue::AddToIncomingQueue [0x000007FEEF150E56+982]
	base::internal::MessageLoopTaskRunner::PostDelayedTask [0x000007FEEF151828+328]
	base::TaskRunner::PostTask [0x000007FEEF0C6043+67]
	base::StackSamplingProfiler::SamplingThread::Add [0x000007FEEF0ADAF2+354]
	base::StackSamplingProfiler::Start [0x000007FEEF0AF986+310]

BUG=773681

Original change's description:
> [Sampling Profiler] Start sampling as early during initialization as possible.
> 
> This will give us visibility into the performance of the earliest parts of
> startup as well as the later parts, which already have coverage.
> 
> R=​asvitkine@chromium.org
> 
> Bug: 700083
> Change-Id: I2fd2e76c00ca46754a57574dc3713ee641494a66
> Reviewed-on: https://chromium-review.googlesource.com/691239


> Reviewed-by: Scott Violet <sky@chromium.org>
> Reviewed-by: Mike Wittman <wittman@chromium.org>
> Reviewed-by: Alexei Svitkine <asvitkine@chromium.org>
> Commit-Queue: Ilya Sherman <isherman@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#507843}

TBR=sky@chromium.org,wittman@chromium.org,isherman@chromium.org,asvitkine@chromium.org

Change-Id: I28d3080b0fa47b953e9a8707511e8cf9bd05ed2d
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 700083
Reviewed-on: https://chromium-review.googlesource.com/712854


Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Cr-Commit-Position: refs/heads/master@{#507976}