Re-adding analytical GeoProc for rectangles

src/gpu/batches/GrAnalyticRectBatch.h

+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef GrAnalyticRectBatch_DEFINED
+#define GrAnalyticRectBatch_DEFINED
+
+#include "GrColor.h"
+
+class GrDrawBatch;
+class SkMatrix;
+struct SkRect;
+
+/*
+ * This class wraps helper functions that draw rects analytically. Used when a shader requires a
+ * distance vector.
+ *
+ * @param color        the shape's color
+ * @param viewMatrix   the shape's local matrix
+ * @param rect         the shape in source space
+ * @param croppedRect  the shape in device space, clipped to the device's bounds
+ * @param bounds       the axis aligned bounds of the shape in device space
+ */
+class GrAnalyticRectBatch {
+public:
+    static GrDrawBatch* CreateAnalyticRectBatch(GrColor color,
+                                                const SkMatrix& viewMatrix,
+                                                const SkRect& rect,
+                                                const SkRect& croppedRect,
+                                                const SkRect& bounds);
+};
+
+#endif // GrAnalyticRectBatch_DEFINED