Add spellcheck and word suggestion to the prediction service

services/prediction/key_set.cc

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "services/prediction/key_set.h"
+
+namespace prediction {
+
+int KeySet::SquaredDistanceToEdge(int x, int y, Key k) {
+  const int left = k.kx;
+  const int right = left + k.kwidth;
+  const int top = k.ky;
+  const int bottom = top + k.kheight;
+  const int edge_x = x < left ? left : (x > right ? right : x);
+  const int edge_y = y < top ? top : (y > bottom ? bottom : y);
+  const int dx = x - edge_x;
+  const int dy = y - edge_y;
+  return dx * dx + dy * dy;
+}
+
+}  // namespace prediction