Enable building Skia's Lottie engine

Making Skottie available for future CrOS UI work.

Change-Id: I41946a4f0d09099e15bf4d08a64bb566080ff393
Reviewed-on: https://chromium-review.googlesource.com/1160772
Reviewed-by: Mike Reed <reed@chromium.org>
Reviewed-by: Ben Wagner <bungeman@chromium.org>
Commit-Queue: Florin Malita <fmalita@chromium.org>
Cr-Commit-Position: refs/heads/master@{#580374}

skia/BUILD.gn

@@ -20,6 +20,7 @@ if (current_cpu == "mipsel" || current_cpu == "mips64el") {
 
 skia_support_gpu = !is_ios
 skia_support_pdf = !is_ios && enable_basic_printing
+skia_support_skottie = true
 
 declare_args() {
   skia_whitelist_serialized_typefaces = false
@@ -112,6 +113,10 @@ config("skia_config") {
   if (skia_whitelist_serialized_typefaces) {
     defines += [ "SK_WHITELIST_SERIALIZED_TYPEFACES" ]
   }
+
+  if (skia_support_skottie) {
+    include_dirs += [ "//third_party/skia/modules/skottie/include" ]
+  }
 }
 
 # Internal-facing config for Skia library code.
@@ -226,6 +231,10 @@ config("skia_library_config") {
       "/wd4800",  # forcing value to bool 'true/false'(assigning int to bool).
     ]
   }
+
+  if (skia_support_skottie) {
+    include_dirs += [ "//third_party/skia/modules/sksg/include" ]
+  }
 }
 
 import("//third_party/skia/third_party/skcms/skcms.gni")
@@ -393,7 +402,6 @@ component("skia") {
     "//third_party/skia/src/utils/SkCamera.cpp",
     "//third_party/skia/src/utils/SkFrontBufferedStream.cpp",
     "//third_party/skia/src/utils/SkInterpolator.cpp",
-    "//third_party/skia/src/utils/SkOSPath.cpp",
     "//third_party/skia/src/utils/SkParsePath.cpp",
   ]
 
@@ -564,6 +572,12 @@ component("skia") {
     sources += [ "//third_party/skia/src/pdf/SkDocument_PDF_None.cpp" ]
   }
 
+  if (skia_support_skottie) {
+    import("//third_party/skia/modules/skottie/skottie.gni")
+    import("//third_party/skia/modules/sksg/sksg.gni")
+    sources += skia_skottie_sources + skia_skottie_public + skia_sksg_sources
+  }
+
   if (!is_debug) {
     configs -= [ "//build/config/compiler:default_optimization" ]
     configs += [ "//build/config/compiler:optimize_max" ]
@@ -819,6 +833,10 @@ test("skia_unittests") {
       "//third_party/test_fonts",
     ]
   }
+
+  if (skia_support_skottie) {
+    sources += [ "ext/skottie_unittest.cc" ]
+  }
 }
 
 if (!is_ios) {

skia/ext/skottie_unittest.cc

@@ -0,0 +1,56 @@
+// Copyright (c) 2018 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "third_party/skia/include/core/SkPixmap.h"
+#include "third_party/skia/include/core/SkStream.h"
+#include "third_party/skia/include/core/SkSurface.h"
+#include "third_party/skia/modules/skottie/include/Skottie.h"
+
+TEST(Skottie, Basic) {
+  // Just a solid green layer.
+  static constexpr char anim_data[] =
+      "{"
+      "  \"v\" : \"4.12.0\","
+      "  \"fr\": 30,"
+      "  \"w\" : 400,"
+      "  \"h\" : 200,"
+      "  \"ip\": 0,"
+      "  \"op\": 150,"
+      "  \"assets\": [],"
+
+      "  \"layers\": ["
+      "    {"
+      "      \"ty\": 1,"
+      "      \"sw\": 400,"
+      "      \"sh\": 200,"
+      "      \"sc\": \"#00ff00\","
+      "      \"ip\": 0,"
+      "      \"op\": 150"
+      "    }"
+      "  ]"
+      "}";
+
+  SkMemoryStream stream(anim_data, strlen(anim_data));
+  auto anim = skottie::Animation::Make(&stream);
+
+  ASSERT_TRUE(anim);
+  EXPECT_EQ(strcmp(anim->version().c_str(), "4.12.0"), 0);
+  EXPECT_EQ(anim->size().width(), 400.0f);
+  EXPECT_EQ(anim->size().height(), 200.0f);
+  EXPECT_EQ(anim->duration(), 5.0f);
+
+  auto surface = SkSurface::MakeRasterN32Premul(400, 200);
+  anim->seek(0);
+  anim->render(surface->getCanvas());
+
+  SkPixmap pixmap;
+  ASSERT_TRUE(surface->peekPixels(&pixmap));
+
+  for (int i = 0; i < pixmap.width(); ++i) {
+    for (int j = 0; j < pixmap.height(); ++j) {
+      EXPECT_EQ(pixmap.getColor(i, j), 0xff00ff00);
+    }
+  }
+}