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This reverts commit 8fe65f6f.

Reason for revert: Suspecting that it's causing these tests
to fail:

services_unittests
MemoryTracingIntegrationTest.GenerationChangeDoesntReenterMDM

content_browsertests
MemoryTracingTest.BrowserInitiatedDump

See bug 899813

Original change's description:
> Introduce base::trace_event::TraceArguments helper class.
> 
> This CL introduces the TraceArguments helper class to simplify
> the way TRACE_EVENTXXX macro named arguments are passed to the
> trace log. By using a small dedicated data structure, it is
> possible to generate less code at each trace call site,
> compared to the old way that relies on passing 5 specially
> crafted arguments to TraceLog methods.
> 
> For example, this optimization can save about 12 kiB in
> libmonochrome.so for the 32-bit ARM build of Chrome on Android.
> For more details, see corresponding bug entry.
> 
> This CL does the following:
> 
> - Introduce the new class in base/trace_event/trace_arguments.h
> 
> - Move the definition of TraceValue to trace_arguments.h and
>   augment the union with templated methods to support easy
>   initialization from a large set of C++ value types.
> 
> - Add new TraceLog methods to add trace events using an
>   optional TraceArguments parameter, instead of a bag of
>   5 ones (count + names + types + values + convertables).
> 
> - Simplify internal templates using C++11 universal references
>   and std::forward<> to remove special-casing convertable
>   arguments in trace event calls.
> 
> - Remove the now obsolete TraceValueUnion type from trace_event.h
> 
> - Make the TraceEvent class fully C++11 movable, to simplify
>   its usage (this removes the Initialize() and MoveFrom() methods).
> 
> - Update base/trace_event/ code to use TraceArguments and the
>   new TraceEvent move operations.
> 
> - Note that this keeps a few forwarding data types, values and
>   methods to avoid other direct callers from the Chromium tree,
>   these will be updated in future CLs. One Blink header needs
>   to be modified though because it specializes a template
>   defined in trace_arguments.h, to support sending WTF::CString
>   references as trace arguments.
> 
> BUG=898794
> R=​oysteine@chromium.org,chiniforooshan@chromium.org,alexiln@chromium.org
> TBR=primiano@chromium.org,torne@chromium.org
> 
> Change-Id: I8fe2225974f7044515a2f64bdc67f6d36abfe004
> Reviewed-on: https://chromium-review.googlesource.com/c/1298997
> Commit-Queue: David Turner <digit@chromium.org>
> Reviewed-by: Richard Coles <torne@chromium.org>
> Reviewed-by: oysteine <oysteine@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#603500}

TBR=digit@chromium.org,primiano@chromium.org,torne@chromium.org,chiniforooshan@chromium.org,oysteine@chromium.org,alexiln@chromium.org

Change-Id: I165b96fde68d927f966bdb4ed8649dd7bb4dd0f5
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 898794, 899813
Reviewed-on: https://chromium-review.googlesource.com/c/1305250Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Commit-Queue: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#603564}