make pathiter bench a little more realistic
make pathiter bench a little more realistic

Touch the memory that the iterator returns, so we're (slightly) more
sure the compiler isn't eliding code we want to be timing.

Change-Id: I62eb36759413d83fb18f4a6e0bf23d4d98f11999
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/235860
Reviewed-by: Mike Klein <14574f09dfa9b4e14759b88c3426a495a0e627b0@google.com>
Reviewed-by: Florin Malita <a8262bf13ea8c26821e91ea9bca6740a77c96dcd@chromium.org>
Commit-Queue: Mike Reed <f5cabf8735907151a446812c9875d6c0c712d847@google.com>

google/skia,google/skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,google/skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,HalCanary/skia-hc,google/skia,HalCanary/skia-hc,aosp-mirror/platform_external_skia,google/skia,aosp-mirror/platform_external_skia,HalCanary/skia-hc,HalCanary/skia-hc,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,google/skia,google/skia,HalCanary/skia-hc,HalCanary/skia-hc,HalCanary/skia-hc,HalCanary/skia-hc,HalCanary/skia-hc,google/skia,aosp-mirror/platform_external_skia,google/skia,aosp-mirror/platform_external_skia,google/skia,HalCanary/skia-hc