Reland "Add tooling support for dmsaa"

Reland 188443be8d18b270a9f5810448d667e6ba009cb0 without the DMSAA bots
to ensure nothing else changes.

Original change's description:
> Add tooling support for dmsaa
>
> Adds a "fAlwaysAntiAlias" flag to GrContextOptions that can be set from
> tooling code. When dmsaa is set, SkGpuDevice draws everything
> antialiased. Adds new "gldmsaa" and "glesdmsaa" configs and creates bots
> to run them.
>
> Bug: skia:11396
> Change-Id: I165e89434b733f7b02312cea0e6649812528083b
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/384936
> Commit-Queue: Chris Dalton <csmartdalton@google.com>
> Reviewed-by: Brian Salomon <bsalomon@google.com>

TBR=bsalomon@google.com

Bug: skia:11396
Change-Id: Icb45097e0a34543dc577fa32f19a692e90643a35
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/386338
Reviewed-by: Chris Dalton <csmartdalton@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
diff --git a/bench/nanobench.cpp b/bench/nanobench.cpp
index c646319..2cb8b00 100644
--- a/bench/nanobench.cpp
+++ b/bench/nanobench.cpp
@@ -247,6 +247,7 @@
     }
     bool init(SkImageInfo info, Benchmark* bench) override {
         GrContextOptions options = grContextOpts;
+        options.fAlwaysAntialias = config.useDMSAA;
         bench->modifyGrContextOptions(&options);
         this->factory = std::make_unique<GrContextFactory>(options);
         SkSurfaceProps props(this->config.surfaceFlags, kRGB_H_SkPixelGeometry);
@@ -469,6 +470,7 @@
         const auto ctxType = gpuConfig->getContextType();
         const auto ctxOverrides = gpuConfig->getContextOverrides();
         const auto sampleCount = gpuConfig->getSamples();
+        const auto useDMSAA = gpuConfig->getUseDMSAA();
         const auto colorType = gpuConfig->getColorType();
         auto colorSpace = gpuConfig->getColorSpace();
         if (gpuConfig->getSurfType() != SkCommandLineConfigGpu::SurfType::kDefault) {
@@ -499,6 +501,7 @@
             kPremul_SkAlphaType,
             sk_ref_sp(colorSpace),
             sampleCount,
+            useDMSAA,
             ctxType,
             ctxOverrides,
             gpuConfig->getSurfaceFlags()
@@ -517,7 +520,7 @@
             }                                                                  \
             Config config = {                                                  \
                 SkString(#name), Benchmark::backend, color, alpha, colorSpace, \
-                0, kBogusContextType, kBogusContextOverrides, 0                \
+                0, false, kBogusContextType, kBogusContextOverrides, 0         \
             };                                                                 \
             configs->push_back(config);                                        \
             return;                                                            \