Prepare ddl skp rendering for prime time

Change-Id: I87742b8ef043588c4e835ab6ec49b217dd49f829
Reviewed-on: https://skia-review.googlesource.com/114289
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
diff --git a/tools/flags/SkCommonFlags.cpp b/tools/flags/SkCommonFlags.cpp
index 4f89505..b78b7d4 100644
--- a/tools/flags/SkCommonFlags.cpp
+++ b/tools/flags/SkCommonFlags.cpp
@@ -63,6 +63,9 @@
 DEFINE_string(jsons, "jsons", "Directory to read (Bodymovin) jsons from.");
 #endif
 
+DEFINE_int32(ddl, 0, "If > 0, the # of x & y divisions used for DeferredDisplayList-based "
+                     "GPU SKP rendering.");
+
 DEFINE_bool(nativeFonts, true, "If true, use native font manager and rendering. "
                                "If false, fonts will draw as portably as possible.");