Add config options to run different GPU APIs to dm and nanobench

tools/flags/SkCommonFlags.cpp

Index: tools/flags/SkCommonFlags.cpp
diff --git a/tools/flags/SkCommonFlags.cpp b/tools/flags/SkCommonFlags.cpp
index 9783dde373546d8f5c47e6b0f340a1a31e32e8e8..a2da1314fc637575764703f2ff0cdd8de524e2ee 100644
--- a/tools/flags/SkCommonFlags.cpp
+++ b/tools/flags/SkCommonFlags.cpp
@@ -7,11 +7,6 @@
 
 #include "SkCommonFlags.h"
 
-DEFINE_string(config, "565 8888 gpu nonrendering angle hwui ", "Options: "
-              "565 8888 angle debug gpu gpudebug gpudft gpunull hwui mesa "
-              "msaa16 msaa4 nonrendering null nullgpu nvprmsaa16 nvprmsaa4 "
-              "pdf skp svg xps (and maybe more)");
-
 DEFINE_bool(cpu, true, "master switch for running CPU-bound work.");
 
 DEFINE_bool(dryRun, false,
@@ -19,11 +14,6 @@ DEFINE_bool(dryRun, false,
 
 DEFINE_bool(gpu, true, "master switch for running GPU-bound work.");
 
-DEFINE_string(gpuAPI, "", "Force use of specific gpu API.  Using \"gl\" "
-              "forces OpenGL API. Using \"gles\" forces OpenGL ES API. "
-              "Defaults to empty string, which selects the API native to the "
-              "system.");
-
 DEFINE_string(images, "", "Directory of images to decode.");
 
 DEFINE_string2(match, m, nullptr,