Creating framework for drawShadowedPicture

src/core/SkPictureFlat.h

Index: src/core/SkPictureFlat.h
diff --git a/src/core/SkPictureFlat.h b/src/core/SkPictureFlat.h
index 125d4e95e84f9c60528ec39bfb6e92ad32d2e09d..22bd7a6b1f89074ab390eadab6e42e79dc3f1c1f 100644
--- a/src/core/SkPictureFlat.h
+++ b/src/core/SkPictureFlat.h
@@ -17,6 +17,13 @@
 #include "SkPtrRecorder.h"
 #include "SkTDynamicHash.h"
 
+/*
+ * Note: While adding new DrawTypes, it is necessary to add to the end of this list
+ *       and update LAST_DRAWTYPE_ENUM to avoid having the code read older skp's wrong.

[jvanverth1, 2016/07/18 15:02:26]

Nit: No apostrophe.

[vjiaoblack, 2016/07/18 16:51:06]

Done.
Well, it's an arguable grammar issue, right?

Like you'd say "I earned 3 A's and 2 B's" and not "I earned 3 As and 2 Bs". 

But either is clear.

Also, just a q: skp is correct, right? Not "SKP"?

+ *       (which can cause segfaults)
+ *
+ *       Reordering can be done during version updates.
+ */
 enum DrawType {
     UNUSED,
     CLIP_PATH,
@@ -83,7 +90,9 @@ enum DrawType {
 
     TRANSLATE_Z,
 
-    LAST_DRAWTYPE_ENUM = TRANSLATE_Z
+    DRAW_SHADOWED_PICTURE_LIGHTS,
+
+    LAST_DRAWTYPE_ENUM = DRAW_SHADOWED_PICTURE_LIGHTS
 };
 
 // In the 'match' method, this constant will match any flavor of DRAW_BITMAP*