Initial wasm debugger

Bug: skia:
Change-Id: I4d38e60f03bb315dee9c9db655ce168e9b3b475f
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/195580
Commit-Queue: Nathaniel Nifong <nifong@google.com>
Reviewed-by: Kevin Lubick <kjlubick@google.com>
diff --git a/BUILD.gn b/BUILD.gn
index f28e12c..d6bac29 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -1052,6 +1052,35 @@
   }
 }
 
+# DebugCanvas used in experimental/wasm-skp-debugger
+if (target_cpu == "wasm") {
+  static_library("debugcanvas") {
+    public_configs = [ ":skia_public" ]
+
+    include_dirs = [
+      "include/gpu",
+      "include/private",
+      "src/gpu",
+      "src/core",
+      "src/shaders",
+      "src/utils",
+      "tools",
+      "tools/debugger",
+    ]
+
+    sources = [
+      "tools/UrlDataManager.cpp",
+      "tools/debugger/SkDebugCanvas.cpp",
+      "tools/debugger/SkDrawCommand.cpp",
+      "tools/debugger/SkJsonWriteBuffer.cpp",
+    ]
+
+    deps = [
+      ":fontmgr_wasm",
+    ]
+  }
+}
+
 static_library("pathkit") {
   public_configs = [ ":skia_public" ]
   configs += skia_library_configs