Attempt 3: Makes managed mode constrain the height of windows so they don't

ash/wm/window_resizer.cc

Index: ash/wm/window_resizer.cc
diff --git a/ash/wm/window_resizer.cc b/ash/wm/window_resizer.cc
index 9cc1c2ae73c96871525ba6dfc6c85f1a5bddee13..fbb523ca1241df416bbce85f23ac8221cf7c0a6e 100644
--- a/ash/wm/window_resizer.cc
+++ b/ash/wm/window_resizer.cc
@@ -205,13 +205,16 @@ void WindowResizer::Drag(const gfx::Point& location) {
 void WindowResizer::CompleteDrag() {
   if (grid_size_ <= 1 || !did_move_or_resize_)
     return;
-  const gfx::Rect& bounds(window_->bounds());
-  int x = AlignToGrid(bounds.x(), grid_size_);
-  int y = AlignToGrid(bounds.y(), grid_size_);
-  gfx::Rect new_bounds(x, y, bounds.width(), bounds.height());
+  gfx::Rect new_bounds(GetFinalBounds());
   if (new_bounds == window_->bounds())
     return;
 
+  if (new_bounds.size() != window_->bounds().size()) {
+    // Don't attempt to animate a size change.
+    window_->SetBounds(new_bounds);
+    return;
+  }
+
   ui::ScopedLayerAnimationSettings scoped_setter(
       window_->layer()->GetAnimator());
   // Use a small duration since the grid is small.
@@ -256,6 +259,13 @@ gfx::Rect WindowResizer::GetBoundsForDrag(const gfx::Point& location) {
   return new_bounds;
 }
 
+gfx::Rect WindowResizer::GetFinalBounds() {
+  const gfx::Rect& bounds(window_->bounds());
+  int x = AlignToGrid(bounds.x(), grid_size_);
+  int y = AlignToGrid(bounds.y(), grid_size_);
+  return gfx::Rect(x, y, bounds.width(), bounds.height());
+}
+
 gfx::Point WindowResizer::GetOriginForDrag(
     int delta_x,
     int delta_y) const {