Update additional tools to take a GrDirectContext

GM was updated in:
https://skia-review.googlesource.com/c/skia/+/300172 (Make GM::onGpuSetup take a GrDirectContext)

This CL updates: skpbench, nanobench, and some testing infrastructure.

Only minor changes were made to the unit tests as they will be updated
en masse in a follow up cl.

Change-Id: Ieffc98865d4c9fc73e292d3c807ed4ae2081745a
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/300220
Reviewed-by: Adlai Holler <adlai@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
diff --git a/BUILD.gn b/BUILD.gn
index a82555e..a100586 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -1455,6 +1455,8 @@
     sources = [
       "tools/gpu/BackendTextureImageFactory.cpp",
       "tools/gpu/BackendTextureImageFactory.h",
+      "tools/gpu/FlushFinishTracker.cpp",
+      "tools/gpu/FlushFinishTracker.h",
       "tools/gpu/GrContextFactory.cpp",
       "tools/gpu/GrTest.cpp",
       "tools/gpu/MemoryCache.cpp",