viewer: Add a "Path renderer" dropdown menu

BUG=skia:

Change-Id: Ia3ed812d24f0f83631ab238bc418a3c95d49b9dc
Reviewed-on: https://skia-review.googlesource.com/9000
Reviewed-by: Yuqian Li <liyuqian@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
diff --git a/tools/viewer/sk_app/GLWindowContext.cpp b/tools/viewer/sk_app/GLWindowContext.cpp
index 89cd858..ff56ce8 100644
--- a/tools/viewer/sk_app/GLWindowContext.cpp
+++ b/tools/viewer/sk_app/GLWindowContext.cpp
@@ -7,7 +7,6 @@
  */
 
 #include "GrContext.h"
-#include "SkCommonFlagsPathRenderer.h"
 #include "SkSurface.h"
 #include "GLWindowContext.h"
 
@@ -37,11 +36,9 @@
     this->onInitializeContext();
     SkASSERT(nullptr == fContext);
 
-    GrContextOptions ctxOptions;
-    ctxOptions.fGpuPathRenderers = CollectGpuPathRenderersFromFlags();
     fBackendContext.reset(GrGLCreateNativeInterface());
     fContext = GrContext::Create(kOpenGL_GrBackend, (GrBackendContext)fBackendContext.get(),
-                                 ctxOptions);
+                                 fDisplayParams.fGrContextOptions);
     if (!fContext && fDisplayParams.fMSAASampleCount) {
         fDisplayParams.fMSAASampleCount /= 2;
         this->initializeContext();