Revert of Use std::unique_ptr. (patchset #8 id:130001 of https://codereview.chromium.org/1780933003/ )

Reason for revert:
Another Android ambiguity due to implicit bool...

frameworks/base/core/jni/android/graphics/Utils.cpp:110:35: error: call of overloaded 'SkMemoryStream(SkAutoTUnref<SkData>&)' is ambiguous
     return new SkMemoryStream(data);

Original issue's description:
> Use std::unique_ptr.
>
> TBR=reed@google.com
>
> Committed: https://skia.googlesource.com/skia/+/20c1e3abfc681771f73eb19fde7284196e028940
>
> Committed: https://skia.googlesource.com/skia/+/3dd9ed37c24611af86f0fe374bd3698b63f09450

TBR=bungeman@google.com,mtklein@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/1785353002
19 files changed