Revert of SkTime::GetNSecs() (patchset #11 id:200001 of https://codereview.chromium.org/1422513003/ )

Reason for revert:
Times don't look like they make sense on Windows.

Original issue's description:
> SkTime::GetNSecs()
>
>    - Move high-precision wall timers from tools/timer to SkTime.
>    - Implement SkTime::GetMSecs() in terms of SkTime::GetNSecs().
>    - Delete unused tools/timer code.
>
> I have no idea what's going on there in src/animator.
> I don't intend to investigate.
>
> BUG=skia:
>
> Committed: https://skia.googlesource.com/skia/+/70084cbc16ee8162649f2601377feb6e49de0217
>
> CQ_EXTRA_TRYBOTS=client.skia.compile:Build-Ubuntu-GCC-x86_64-Debug-CrOS_Link-Trybot
>
> Committed: https://skia.googlesource.com/skia/+/a1840d50e29fd95e4df2d1168fe54c34c2a5c30c
>
> Committed: https://skia.googlesource.com/skia/+/38a88e4c0c28a7be981aac7bb4a198ad95a62a63

TBR=caryclark@google.com,reed@google.com,mtklein@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review URL: https://codereview.chromium.org/1422623003

1 files changed, 0 insertions, 23 deletions

diff --git a/src/core/SkTime.cpp b/src/core/SkTime.cpp
index 72b9aced51..fa6c04447d 100644
--- a/src/core/SkTime.cpp
+++ b/src/core/SkTime.cpp
@@ -22,26 +22,3 @@ void SkTime::DateTime::toISO8601(SkString* dst) const {
                     timeZoneMinutes);
     }
 }
-
-// TODO: use std::chrono on Mach too, when available.
-
-#if defined(__MACH__)
-    #include "SkOncePtr.h"
-    #include <mach/mach_time.h>
-    SK_DECLARE_STATIC_ONCE_PTR(double, ns_per_tick);
-    double SkTime::GetNSecs() {
-        uint64_t ticks = mach_absolute_time();
-        return ticks * *ns_per_tick.get([]{
-            mach_timebase_info_data_t timebase;
-            (void)mach_timebase_info(&timebase);
-            return new double(timebase.numer * 1.0 / timebase.denom);
-        });
-    }
-#else
-    #include <chrono>
-    double SkTime::GetNSecs() {
-        auto now = std::chrono::high_resolution_clock::now();
-        std::chrono::duration<double, std::nano> ns = now.time_since_epoch();
-        return ns.count();
-    }
-#endif