[canvaskit] Add path/canvas methods

ToCmds/MakePathFromCmds taken from PathKit, as were the tests
for those methods.

Bug: skia:
Change-Id: I9c52c04fe61e8934543a10f84ebf8b01b449f7f4
Reviewed-on: https://skia-review.googlesource.com/c/181565
Reviewed-by: Kevin Lubick <kjlubick@google.com>
diff --git a/modules/pathkit/tests/path.spec.js b/modules/pathkit/tests/path.spec.js
index 0930fa6..80a779a 100644
--- a/modules/pathkit/tests/path.spec.js
+++ b/modules/pathkit/tests/path.spec.js
@@ -159,7 +159,7 @@
     }
 
     describe('Command arrays', function(){
-        it('does NOT approximates conics when dumping as toCmds', function(done){
+        it('does NOT approximates conics when dumping as toCmds', function(done) {
             LoadPathKit.then(catchException(done, () => {
                 let path = PathKit.NewPath();
                 path.moveTo(20, 120);