Revert "Re-enable NVPR on flutter."

This reverts commit f9c5ca41190fe7d8342c87ffc3f4b8e304defeea.

Reason for revert: The potential root cause of the fucshia roll failure
was removed in https://skia-review.googlesource.com/c/skia/+/162022/11/src/gpu/GrPathRendering_none.cpp

Original change's description:
> Re-enable NVPR on flutter.
> 
> This hopefully fixes fuchsia roll.
> 
> Bug: skia:
> Change-Id: I5c5f28413e45f46e94d54ce75ef5fb19fca32347
> Reviewed-on: https://skia-review.googlesource.com/c/162581
> Reviewed-by: Brian Osman <brianosman@google.com>

TBR=egdaniel@google.com,brianosman@google.com

Change-Id: Iebba700752560b65f20e873910b38be8295e69bf
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:
Reviewed-on: https://skia-review.googlesource.com/c/163122
Reviewed-by: Mike Klein <mtklein@google.com>
Commit-Queue: Kevin Lubick <kjlubick@google.com>
diff --git a/BUILD.gn b/BUILD.gn
index fe6dc75..b0e9191 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -39,7 +39,7 @@
 
   skia_android_serial = ""
   skia_enable_ccpr = true
-  skia_enable_nvpr = true  # TODO: !skia_enable_flutter_defines
+  skia_enable_nvpr = !skia_enable_flutter_defines
   skia_enable_discrete_gpu = true
   skia_enable_effects = true
   skia_enable_effects_imagefilters = true