SkMojo: test linking Skia against the Mojo SDK

TODO: build on systems other than Linux.

Add mojo_skd to the DEPS.

Add a DM::Via called `mojo-`.

everything is hidden behind the gyp variable `skia_mojo`.
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1644043003

Review URL: https://codereview.chromium.org/1644043003

3 files changed, 60 insertions, 0 deletions

diff --git a/dm/DM.cpp b/dm/DM.cpp
index cdd53c6be4..538e2f6dc6 100644
--- a/dm/DM.cpp
+++ b/dm/DM.cpp
@@ -691,6 +691,7 @@ static Sink* create_via(const SkString& tag, Sink* wrapped) {
     VIA("tiles_rt",  ViaTiles, 256, 256, new SkRTreeFactory, wrapped);
     VIA("remote",       ViaRemote, false, wrapped);
     VIA("remote_cache", ViaRemote, true,  wrapped);
+    VIA("mojo",      ViaMojo,             wrapped);
 
     if (FLAGS_matrix.count() == 4) {
         SkMatrix m;
diff --git a/dm/DMSrcSink.cpp b/dm/DMSrcSink.cpp
index 9712fd73a0..f5a00b5600 100644
--- a/dm/DMSrcSink.cpp
+++ b/dm/DMSrcSink.cpp
@@ -31,6 +31,10 @@
 #include "SkSwizzler.h"
 #include <functional>
 
+#ifdef SK_MOJO
+    #include "SkMojo.mojom.h"
+#endif
+
 DEFINE_bool(multiPage, false, "For document-type backends, render the source"
             " into multiple pages");
 
@@ -1230,6 +1234,55 @@ Error ViaTwice::draw(const Src& src, SkBitmap* bitmap, SkWStream* stream, SkStri
 
 /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
 
+#ifdef SK_MOJO
+    Error ViaMojo::draw(const Src& src, SkBitmap* bitmap, SkWStream* stream, SkString* log) const {
+        SkPictureRecorder recorder;
+        SkRect size = SkRect::Make(SkIRect::MakeSize(src.size()));
+        Error err = src.draw(recorder.beginRecording(size));
+        if (!err.isEmpty()) {
+            return err;
+        }
+        SkAutoTUnref<SkPicture> skPicture(recorder.endRecording());
+
+        SkASSERT(skPicture);
+        SkDynamicMemoryWStream buffer;
+        skPicture->serialize(&buffer);
+        skPicture.reset();
+        SkMojo::FlattenedPicturePtr mojoPicture = SkMojo::FlattenedPicture::New();
+        mojoPicture->data.resize(buffer.bytesWritten());
+        buffer.copyTo(mojoPicture->data.data());
+        buffer.reset();
+        SkASSERT(mojoPicture.get() && mojoPicture->data);
+
+        size_t flatSize = mojoPicture->GetSerializedSize();
+        SkAutoMalloc storage(flatSize);
+        if (!mojoPicture->Serialize(storage.get(), flatSize)) {
+            return "SkMojo::FlattenedPicture::Serialize failed";
+        }
+        mojoPicture = SkMojo::FlattenedPicture::New();
+        mojoPicture->Deserialize(storage.get());
+        storage.free();
+        if (!mojoPicture) {
+            return "SkMojo::FlattenedPicture::Deserialize failed";
+        }
+        SkMemoryStream tmpStream(mojoPicture->data.data(),
+                                 mojoPicture->data.size());
+        skPicture.reset(SkPicture::CreateFromStream(&tmpStream));
+        mojoPicture.reset();
+        auto fn = [&](SkCanvas* canvas) -> Error {
+            canvas->drawPicture(skPicture.get());
+            return check_against_reference(bitmap, src, fSink);
+        };
+        return draw_to_canvas(fSink, bitmap, stream, log, src.size(), fn);
+    }
+#else // not SK_MOJO
+    Error ViaMojo::draw(const Src&, SkBitmap*, SkWStream*, SkString*) const {
+        return "Mojo is missing!";
+    }
+#endif
+
+/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
+
 // This is like SkRecords::Draw, in that it plays back SkRecords ops into a Canvas.
 // Unlike SkRecords::Draw, it builds a single-op sub-picture out of each Draw-type op.
 // This is an only-slightly-exaggerated simluation of Blink's Slimming Paint pictures.
diff --git a/dm/DMSrcSink.h b/dm/DMSrcSink.h
index a719bd154a..3a7d4ee516 100644
--- a/dm/DMSrcSink.h
+++ b/dm/DMSrcSink.h
@@ -357,6 +357,12 @@ public:
     Error draw(const Src&, SkBitmap*, SkWStream*, SkString*) const override;
 };
 
+class ViaMojo : public Via {
+public:
+    explicit ViaMojo(Sink* sink) : Via(sink) {}
+    Error draw(const Src&, SkBitmap*, SkWStream*, SkString*) const override;
+};
+
 }  // namespace DM
 
 #endif//DMSrcSink_DEFINED