YogaLayout perf tests

Summary: We would like to know some numbers on benchmarking `YogaLayout` against other layouts, particularly `LinearLayout`.  This implements a `BenchmarkActivity` to fill that need.

Reviewed By: emilsjolander

Differential Revision: D4565531

fbshipit-source-id: fe1c558beb603c3116ac3d0dd6654b0376dd6b8a

android/sample/java/com/facebook/samples/yoga/BenchmarkInflate.java

@@ -0,0 +1,65 @@
+// Copyright 2004-present Facebook. All Rights Reserved.
+
+package com.facebook.samples.yoga;
+
+import android.os.Bundle;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.widget.TextView;
+import android.widget.Button;
+import android.view.ViewGroup;
+import android.util.Log;
+import com.facebook.samples.yoga.R;
+
+public class BenchmarkInflate extends BenchmarkFragment {
+
+  @Override
+  public View onCreateView(
+    LayoutInflater inflater,
+    ViewGroup container,
+    Bundle savedInstanceState) {
+    super.onCreateView(inflater, container, savedInstanceState);
+
+    Button b = (Button) rootLayout.findViewById(R.id.btn);
+    b.setOnClickListener(new View.OnClickListener() {
+      @Override
+      public void onClick(View v) {
+        startBenchmark();
+      }
+    });
+
+    return rootLayout;
+  }
+
+  protected void startBenchmark() {
+    LayoutInflater inflater = LayoutInflater.from(getActivity());
+    TextView textView = (TextView) rootLayout.findViewById(R.id.text);
+
+    final int ITERATIONS = 500;
+
+    inflater.inflate(yogaLayout, null);
+    inflater.inflate(linearLayout, null);
+
+    BenchmarkAggregator yogaInflationAggregator = new BenchmarkAggregator("Yoga Inflate");
+    BenchmarkAggregator linearInflationAggregator = new BenchmarkAggregator("Linear Inflate");
+    for (int i = 0; i < ITERATIONS; i++) {
+      yogaInflationAggregator.startTrace();
+      inflater.inflate(yogaLayout, null);
+      yogaInflationAggregator.endTrace();
+      linearInflationAggregator.startTrace();
+      inflater.inflate(linearLayout, null);
+      linearInflationAggregator.endTrace();
+    }
+
+    textView.setText(
+        yogaInflationAggregator.toString()+
+            "\n"+
+            linearInflationAggregator.toString());
+    Log.i(
+      "YogaLayoutBenchmark",
+      yogaInflationAggregator.toString()+
+        "\n"+
+        linearInflationAggregator.toString());
+    rootLayout.invalidate();
+  }
+}