Avoid divide by zero when animating panel bounds.

chrome/browser/ui/panels/panel_bounds_animation.cc

 // Copyright (c) 2011 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 "chrome/browser/ui/panels/panel_bounds_animation.h"
 
 #include "chrome/browser/ui/panels/panel.h"
 #include "chrome/browser/ui/panels/panel_manager.h"
 
 namespace {
@@ skipping 11 matching lines @@
                                            const gfx::Rect& final_bounds)
     : ui::LinearAnimation(kDefaultFramerateHz, target),
       panel_(panel),
       for_big_minimize_(false),
       animation_stop_to_show_titlebar_(0) {
   // Detect animation that happens when expansion state is set to MINIMIZED
   // and there is relatively big portion of the panel to hide from view.
   // Initialize animation differently in this case, using fast-pause-slow
   // method, see below for more details.
   int duration = kSetBoundsAnimationMs;
-  if (panel_->expansion_state() == Panel::MINIMIZED) {
+  if (initial_bounds.height() > final_bounds.height() &&
+      panel_->expansion_state() == Panel::MINIMIZED) {
     double hidden_title_height =
         panel_->TitleOnlyHeight() - final_bounds.height();
     double distance_y = initial_bounds.height() - final_bounds.height();
     animation_stop_to_show_titlebar_ = 1.0 - hidden_title_height / distance_y;
     if (animation_stop_to_show_titlebar_ > 0.7) {  // Relatively big movement.
       for_big_minimize_ = true;
       duration = kSetBoundsAnimationBigMinimizeMs;
     }
   }
   SetDuration(PanelManager::AdjustTimeInterval(duration));
@@ skipping 28 matching lines @@
         (progress / kProgressAtFreezeStart);
   } else if (progress <= kProgressAtFreezeEnd) {
     value = animation_stop_to_show_titlebar;
   } else {
     value = animation_stop_to_show_titlebar +
         (1.0 - animation_stop_to_show_titlebar) *
         ((progress - kProgressAtFreezeEnd) / (1.0 - kProgressAtFreezeEnd));
   }
   return value;
 }