Add ContextOptions field to SkCommandLineConfigGpu

Reduces duplicate code by computing the ContextOptions in one spot.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2337163002

Review-Url: https://codereview.chromium.org/2337163002
diff --git a/tools/skiaserve/Request.cpp b/tools/skiaserve/Request.cpp
index ea2d17a..ef1f757 100644
--- a/tools/skiaserve/Request.cpp
+++ b/tools/skiaserve/Request.cpp
@@ -72,10 +72,10 @@
 #if SK_SUPPORT_GPU
     GrContextFactory* factory = fContextFactory;
     GLTestContext* gl = factory->getContextInfo(GrContextFactory::kNativeGL_ContextType,
-                                                GrContextFactory::kNone_ContextOptions).glContext();
+                                               GrContextFactory::ContextOptions::kNone).glContext();
     if (!gl) {
         gl = factory->getContextInfo(GrContextFactory::kMESA_ContextType,
-                                     GrContextFactory::kNone_ContextOptions).glContext();
+                                     GrContextFactory::ContextOptions::kNone).glContext();
     }
     if (gl) {
         gl->makeCurrent();
@@ -123,10 +123,10 @@
 GrContext* Request::getContext() {
 #if SK_SUPPORT_GPU
     GrContext* result = fContextFactory->get(GrContextFactory::kNativeGL_ContextType,
-                                             GrContextFactory::kNone_ContextOptions);
+                                             GrContextFactory::ContextOptions::kNone);
     if (!result) {
         result = fContextFactory->get(GrContextFactory::kMESA_ContextType,
-                                      GrContextFactory::kNone_ContextOptions);
+                                      GrContextFactory::ContextOptions::kNone);
     }
     return result;
 #else