Removes aura dependencies from WindowPositioner

ash/wm/common/window_positioning_utils.cc

Index: ash/wm/common/window_positioning_utils.cc
diff --git a/ash/wm/common/window_positioning_utils.cc b/ash/wm/common/window_positioning_utils.cc
new file mode 100644
index 0000000000000000000000000000000000000000..7ba629babc2eadcc9004da5bf1fd6c96bde662ad
--- /dev/null
+++ b/ash/wm/common/window_positioning_utils.cc
@@ -0,0 +1,50 @@
+// Copyright 2016 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 "ash/wm/common/window_positioning_utils.h"
+
+#include <algorithm>
+
+#include "ui/gfx/geometry/rect.h"
+#include "ui/gfx/geometry/size.h"
+
+namespace ash {
+namespace wm {
+
+void AdjustBoundsSmallerThan(const gfx::Size& max_size, gfx::Rect* bounds) {
+  bounds->set_width(std::min(bounds->width(), max_size.width()));
+  bounds->set_height(std::min(bounds->height(), max_size.height()));
+}
+
+void AdjustBoundsToEnsureWindowVisibility(const gfx::Rect& visible_area,
+                                          int min_width,
+                                          int min_height,
+                                          gfx::Rect* bounds) {
+  AdjustBoundsSmallerThan(visible_area.size(), bounds);
+
+  min_width = std::min(min_width, visible_area.width());
+  min_height = std::min(min_height, visible_area.height());
+
+  if (bounds->right() < visible_area.x() + min_width) {
+    bounds->set_x(visible_area.x() + min_width - bounds->width());
+  } else if (bounds->x() > visible_area.right() - min_width) {
+    bounds->set_x(visible_area.right() - min_width);
+  }
+  if (bounds->bottom() < visible_area.y() + min_height) {
+    bounds->set_y(visible_area.y() + min_height - bounds->height());
+  } else if (bounds->y() > visible_area.bottom() - min_height) {
+    bounds->set_y(visible_area.bottom() - min_height);
+  }
+  if (bounds->y() < visible_area.y())
+    bounds->set_y(visible_area.y());
+}
+
+void AdjustBoundsToEnsureMinimumWindowVisibility(const gfx::Rect& visible_area,
+                                                 gfx::Rect* bounds) {
+  AdjustBoundsToEnsureWindowVisibility(visible_area, kMinimumOnScreenArea,
+                                       kMinimumOnScreenArea, bounds);
+}
+
+}  // namespace wm
+}  // namespace ash