Add Perf jobs for PathKit

We have a similar ingestion strategy to Gold.

I tried to use something off the shelf like benchmark.js
but passing the PathKit context into the benchmarks was
non-trivial. Plus, making a basic benchmarking tool
ended up being not too hard.

We should be able to re-use the docker container/aggregator
for CanvasKit too.

Bug: skia:
Change-Id: I613dfc58ea57c31cf71566a8ac55f8df9272ad25
Reviewed-on: https://skia-review.googlesource.com/c/161620
Commit-Queue: Kevin Lubick <kjlubick@google.com>
Reviewed-by: Joe Gregorio <jcgregorio@google.com>
Reviewed-by: Stephan Altmueller <stephana@google.com>
diff --git a/modules/pathkit/helper.js b/modules/pathkit/helper.js
index 51e1ffd..82713ba 100644
--- a/modules/pathkit/helper.js
+++ b/modules/pathkit/helper.js
@@ -63,7 +63,10 @@
   // See above for example of cmds.
   PathKit.FromCmds = function(cmds) {
     var ptrLen = PathKit.loadCmdsTypedArray(cmds);
-    return PathKit._FromCmds(ptrLen[0], ptrLen[1]);
+    var path = PathKit._FromCmds(ptrLen[0], ptrLen[1]);
+    // TODO(kjlubick): cache this memory blob somehow.
+    PathKit._free(ptrLen[0]);
+    return path;
   }
 
   /**