deferred canvas

dm/DMSrcSink.cpp

Index: dm/DMSrcSink.cpp
diff --git a/dm/DMSrcSink.cpp b/dm/DMSrcSink.cpp
index f0b10103f7494d17a97ccb4bbbdde447a8afaa61..1b5d0cfbe06c070fb742ac00ff61e0d32a8f856f 100644
--- a/dm/DMSrcSink.cpp
+++ b/dm/DMSrcSink.cpp
@@ -15,6 +15,7 @@
 #include "SkColorSpaceXform.h"
 #include "SkCommonFlags.h"
 #include "SkData.h"
+#include "SkDeferredCanvas.h"
 #include "SkDocument.h"
 #include "SkError.h"
 #include "SkImageGenerator.h"
@@ -49,6 +50,8 @@ DEFINE_bool(multiPage, false, "For document-type backends, render the source"
             " into multiple pages");
 DEFINE_bool(RAW_threading, true, "Allow RAW decodes to run on multiple threads?");
 
+extern bool gUseDeferredCanvas;
+
 using sk_gpu_test::GrContextFactory;
 
 namespace DM {
@@ -1229,7 +1232,8 @@ Error RasterSink::draw(const Src& src, SkBitmap* dst, SkWStream*, SkString*) con
                      &factory,
                      nullptr/*colortable*/);
     SkCanvas canvas(*dst);
-    return src.draw(&canvas);
+    SkDeferredCanvas deferred(&canvas);
+    return src.draw(gUseDeferredCanvas ? &deferred : &canvas);
 }
 
 /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
@@ -1400,6 +1404,13 @@ Error ViaTiles::draw(const Src& src, SkBitmap* bitmap, SkWStream* stream, SkStri
                 auto s = canvas->makeSurface(info);
                 if (!s) {
                     s = SkSurface::MakeRaster(info);  // Some canvases can't create surfaces.
+                    if (!s) {
+                        // non-pixel canvases return unknown colortype, which would make
+                        // makesurface fail, so assume that is why we failed, and use N32.
+                        SkASSERT(kUnknown_SkColorType == info.colorType());
+                        info = SkImageInfo::MakeN32Premul(info.width(), info.height());
+                        s = SkSurface::MakeRaster(info);
+                    }
                 }
                 surfaces.push_back(s);
                 SkCanvas* c = s->getCanvas();