Add a method in SkCanvas to set "hard" clip bounds.

Add SkCanvas::setBoundRect, which sets the max clip rectangle,
which can be replaced by clipRect, clipRRect and clipPath.

BUG=skia:

Change-Id: Ie39eb1715214971576e7a1dda760c6997a7e0208
Reviewed-on: https://skia-review.googlesource.com/5359
Commit-Queue: Stan Iliev <stani@google.com>
Reviewed-by: Mike Reed <reed@google.com>
Reviewed-by: Derek Sollenberger <djsollen@google.com>
diff --git a/gn/gm.gni b/gn/gm.gni
index 41a75ff..e73c1a5 100644
--- a/gn/gm.gni
+++ b/gn/gm.gni
@@ -73,6 +73,7 @@
   "$_gm/complexclip_blur_tiled.cpp",
   "$_gm/complexclip2.cpp",
   "$_gm/complexclip3.cpp",
+  "$_gm/complexclip4.cpp",
   "$_gm/composeshader.cpp",
   "$_gm/concavepaths.cpp",
   "$_gm/conicpaths.cpp",