Conservative update button/label/textfield content

ui/views/controls/label.cc

 // Copyright (c) 2012 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/label.h"
 
 #include <algorithm>
 #include <cmath>
 #include <limits>
 #include <vector>
@@ skipping 36 matching lines @@
 }
 
 void Label::SetFont(const gfx::Font& font) {
   font_ = font;
   text_size_valid_ = false;
   PreferredSizeChanged();
   SchedulePaint();
 }
 
 void Label::SetText(const string16& text) {
-  text_ = text;
-  text_size_valid_ = false;
-  is_email_ = false;
-  PreferredSizeChanged();
-  SchedulePaint();
+  if (text != text_) {

[Daniel Erat, 2012/09/11 20:53:37]

nit: same here

+    text_ = text;
+    text_size_valid_ = false;
+    is_email_ = false;
+    PreferredSizeChanged();
+    SchedulePaint();
+  }
 }
 
 void Label::SetEmail(const string16& email) {
   SetText(email);
   is_email_ = true;
 }
 
 void Label::SetAutoColorReadabilityEnabled(bool enabled) {
   auto_color_readability_ = enabled;
   RecalculateColors();
@@ skipping 421 matching lines @@
                                 ui::ELIDE_AT_END);
   } else {
     *paint_text = text_;
   }
 
   *text_bounds = GetTextBounds();
   *flags = ComputeDrawStringFlags();
 }
 
 }  // namespace views