Revert of Revert of Turn on NVPR 4x MSAA by default when supported in DM and nanobench. (patchset #1 id:1 of https://codereview.chromium.org/693933004/)

Reason for revert:
Try again with loops overflow fix landed.

Original issue's description:
> Revert of Turn on NVPR 4x MSAA by default when supported in DM and nanobench. (patchset #2 id:20001 of https://codereview.chromium.org/704563003/)
>
> Reason for revert:
> Timing out on nvpr when drawing conics. Fix will take some thought so reverting for now.
>
> Original issue's description:
> > Turn on NVPR 4x MSAA by default when supported in DM and nanobench.
> >
> > This brings DM and nanobench's default configs in line with GM's.
> >
> > BUG=skia:
> >
> > Committed: https://skia.googlesource.com/skia/+/31f88675718966bbb7f09718b40de10c7e214739
>
> TBR=bsalomon@google.com,mtklein@google.com,mtklein@chromium.org
> NOTREECHECKS=true
> NOTRY=true
> BUG=skia:
>
> Committed: https://skia.googlesource.com/skia/+/d5cd4ee5b81b51e43be7ed13f3c0f0f6c1b3fe14

TBR=bsalomon@google.com,mtklein@chromium.org,egdaniel@google.com
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review URL: https://codereview.chromium.org/685923003
diff --git a/tools/flags/SkCommonFlags.cpp b/tools/flags/SkCommonFlags.cpp
index 99d05c1..4d329c5 100644
--- a/tools/flags/SkCommonFlags.cpp
+++ b/tools/flags/SkCommonFlags.cpp
@@ -7,7 +7,7 @@
 
 #include "SkCommonFlags.h"
 
-DEFINE_string(config, "565 8888 pdf gpu nonrendering angle",
+DEFINE_string(config, "565 8888 pdf gpu nonrendering angle nvprmsaa4",
               "Options: 565 8888 pdf gpu nonrendering msaa4 msaa16 nvprmsaa4 nvprmsaa16 "
               "gpunull gpudebug angle mesa");