Import new C source of truth css-layout

fbshipit-source-id: e866918d6c62fc1cf3a04c269f782b94db9b875a

java/com/facebook/csslayout/CSSLayout.java

@@ -0,0 +1,77 @@
+/**
+ * Copyright (c) 2014-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+package com.facebook.csslayout;
+
+import java.util.Arrays;
+
+/**
+ * Where the output of {@link LayoutEngine#layoutNode(CSSNode, float)} will go in the CSSNode.
+ */
+public class CSSLayout {
+  // This value was chosen based on empiracle data. Even the most complicated
+  // layouts should not require more than 16 entries to fit within the cache.
+  public static final int MAX_CACHED_RESULT_COUNT = 16;
+
+  public static final int POSITION_LEFT = 0;
+  public static final int POSITION_TOP = 1;
+  public static final int POSITION_RIGHT = 2;
+  public static final int POSITION_BOTTOM = 3;
+
+  public static final int DIMENSION_WIDTH = 0;
+  public static final int DIMENSION_HEIGHT = 1;
+
+  public float[] position = new float[4];
+  public float[] dimensions = new float[2];
+  public CSSDirection direction = CSSDirection.LTR;
+
+  public float flexBasis;
+
+  public int generationCount;
+  public CSSDirection lastParentDirection;
+
+  public int nextCachedMeasurementsIndex;
+  public CSSCachedMeasurement[] cachedMeasurements = new CSSCachedMeasurement[MAX_CACHED_RESULT_COUNT];
+  public float[] measuredDimensions = new float[2];
+
+  public CSSCachedMeasurement cachedLayout = new CSSCachedMeasurement();
+
+  CSSLayout() {
+    resetResult();
+  }
+
+  public void resetResult() {
+    Arrays.fill(position, 0);
+    Arrays.fill(dimensions, CSSConstants.UNDEFINED);
+    direction = CSSDirection.LTR;
+
+    flexBasis = 0;
+
+    generationCount = 0;
+    lastParentDirection = null;
+
+    nextCachedMeasurementsIndex = 0;
+    measuredDimensions[DIMENSION_WIDTH] = CSSConstants.UNDEFINED;
+    measuredDimensions[DIMENSION_HEIGHT] = CSSConstants.UNDEFINED;
+
+    cachedLayout.widthMeasureMode = null;
+    cachedLayout.heightMeasureMode = null;
+  }
+
+  @Override
+  public String toString() {
+    return "layout: {" +
+        "left: " + position[POSITION_LEFT] + ", " +
+        "top: " + position[POSITION_TOP] + ", " +
+        "width: " + dimensions[DIMENSION_WIDTH] + ", " +
+        "height: " + dimensions[DIMENSION_HEIGHT] + ", " +
+        "direction: " + direction +
+        "}";
+  }
+}