de-common --veryVerbose

In the end only DM and skia_test really use it.

 - nanobench used --veryVerbose in a silly superficial way
 - gm/fontmgr.cpp is probably clearer using its own flag
 - the change to StrokerTest should be a near noop...
   reporter->verbose() is set by --veryVerbose in both
   DM and skia_test.cpp.  One of the checks tested
   FLAGS_verbose, but I feel like that was probably a typo.

Change-Id: I2601d243b8200b3bb7a16478dfbce14001c4a191
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/203180
Commit-Queue: Mike Klein <mtklein@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
7 files changed