Revert "Switch DDL rendering to be a Via in DM"

This reverts commit bd2e2a0cafb0944255635b95663e1d242064b9c3.

Reason for revert: 

Build-Debian9-Clang-x86_64-Debug-MSAN

In file included from ../../../dm/DMSrcSink.cpp:8:
../../../dm/DMSrcSink.h:548:15: error: private field 'fNumDivisions' is not used [-Werror,-Wunused-private-field]
    const int fNumDivisions;

Original change's description:
> Switch DDL rendering to be a Via in DM
> 
> This will let us also render the GMs via DDLs.
> 
> Change-Id: I866a5af66d737473f4760dbc9d45053460c42e6e
> Reviewed-on: https://skia-review.googlesource.com/116021
> Commit-Queue: Robert Phillips <robertphillips@google.com>
> Reviewed-by: Greg Daniel <egdaniel@google.com>
> Reviewed-by: Mike Klein <mtklein@google.com>

TBR=egdaniel@google.com,mtklein@google.com,robertphillips@google.com

Change-Id: Ice07c25ab29c57b2efb193c03e5504a2ae1a0743
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/116560
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
5 files changed