Add pre_log option to nanobench; make this option default true in nanobench_flags.py and dm_flags.py.

BUG=skia:4826
BUG=skia:4827
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1612483002

Review URL: https://codereview.chromium.org/1612483002

1 files changed, 6 insertions, 0 deletions

diff --git a/bench/nanobench.cpp b/bench/nanobench.cpp
index 4fc4044449..cfedc52379 100644
--- a/bench/nanobench.cpp
+++ b/bench/nanobench.cpp
@@ -1124,6 +1124,12 @@ int nanobench_main() {
             SkCanvas* canvas = target->getCanvas();
             const char* config = target->config.name;
 
+            if (FLAGS_pre_log) {
+                SkDebugf("Running %s\t%s\n"
+                         , bench->getUniqueName()
+                         , config);
+            }
+
             target->setup();
             bench->perCanvasPreDraw(canvas);