views: Make view::Views::GetPreferredSize() const.

ui/views/controls/styled_label.cc

 // Copyright 2013 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 "ui/views/controls/styled_label.h"
 
 #include <vector>
 
 #include "base/strings/string_util.h"
 #include "ui/gfx/font_list.h"
@@ skipping 139 matching lines @@
           Label::kFocusBorderPadding, Label::kFocusBorderPadding,
           Label::kFocusBorderPadding, Label::kFocusBorderPadding);
       insets += focus_border_padding;
       break;
     }
   }
 
   return insets;
 }
 
-int StyledLabel::GetHeightForWidth(int w) {
-  if (w != calculated_size_.width())
-    calculated_size_ = CalculateAndDoLayout(w, true);
+int StyledLabel::GetHeightForWidth(int w) const {
+  if (w != calculated_size_.width()) {
+    // TODO(erg): Munge the const-ness of the style label. CalculateAndDoLayout
+    // doesn't actually make any changes to member variables when |dry_run| is
+    // set to true. In general, the mutating and non-mutating parts shouldn't
+    // be in the same codepath.
+    //
+    // I only feel OK about this quick hack since this code is going away

[sky, 2014/05/13 16:13:57]

Why is this code going away?

[Elliot Glaysher, 2014/05/14 00:48:58]

I actually got the wrong impression from msw@. This code has no plans to go
away.

I still don't like it, but I guess a const_cast<> here isn't the end of the
world.

+    // anyway?
+    calculated_size_ =
+        const_cast<StyledLabel*>(this)->CalculateAndDoLayout(w, true);
+  }
   return calculated_size_.height();
 }
 
 void StyledLabel::Layout() {
   calculated_size_ = CalculateAndDoLayout(GetLocalBounds().width(), false);
 }
 
 void StyledLabel::PreferredSizeChanged() {
   calculated_size_ = gfx::Size();
   View::PreferredSizeChanged();
@@ skipping 127 matching lines @@
     }
     x += view_size.width() - focus_border_insets.width();
 
     remaining_string = remaining_string.substr(chunk.size());
   }
 
   return gfx::Size(width, (line + 1) * line_height + GetInsets().height());
 }
 
 }  // namespace views