Fixes couple of bugs in the TabStrip that could cause tabs to dance

chrome/browser/ui/views/tabs/tab_strip.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 "chrome/browser/ui/views/tabs/tab_strip.h"
 
 #if defined(OS_WIN)
 #include <windowsx.h>
 #endif
 
@@ skipping 1071 matching lines @@
   // It doesn't make sense to drag tabs out on Win8's single window Metro mode.
   if (win8::IsSingleWindowMetroMode())
     detach_behavior = TabDragController::NOT_DETACHABLE;
 #endif
   // Gestures don't automatically do a capture. We don't allow multiple drags at
   // the same time, so we explicitly capture.
   if (event.type() == ui::ET_GESTURE_BEGIN)
     GetWidget()->SetCapture(this);
   drag_controller_.reset(new TabDragController);
   drag_controller_->Init(
-      this, tab, tabs, gfx::Point(x, y), tab->GetMirroredXInView(event.x()),
+      this, tab, tabs, gfx::Point(x, y), event.x(),
       selection_model, detach_behavior, move_behavior);
 }
 
 void TabStrip::ContinueDrag(views::View* view, const gfx::Point& location) {
   if (drag_controller_.get()) {
     gfx::Point screen_location(location);
     views::View::ConvertPointToScreen(view, &screen_location);
     drag_controller_->Drag(screen_location);
   }
 }
@@ skipping 1014 matching lines @@
   RemoveMessageLoopObserver();
 
   in_tab_close_ = false;
   available_width_for_tabs_ = -1;
   int mini_tab_count = GetMiniTabCount();
   if (mini_tab_count == tab_count()) {
     // Only mini-tabs, we know the tab widths won't have changed (all
     // mini-tabs have the same width), so there is nothing to do.
     return;
   }
-  Tab* first_tab  = tab_at(mini_tab_count);
-  double unselected, selected;
-  GetDesiredTabWidths(tab_count(), mini_tab_count, &unselected, &selected);
-  // TODO: this is always selected, should it be 'selected : unselected'?
-  int w = Round(first_tab->IsActive() ? selected : selected);
-
-  // We only want to run the animation if we're not already at the desired
-  // size.
-  if (abs(first_tab->width() - w) > 1)
-    StartResizeLayoutAnimation();
+  // Don't try and avoid layout based on tab sizes. If tabs are small enough
+  // then the width of the active tab may not change, but other widths may
+  // have. This is particularly important if we've overflowed (all tabs are at
+  // the min).
+  StartResizeLayoutAnimation();
 }
 
 void TabStrip::ResizeLayoutTabsFromTouch() {
   // Don't resize if the user is interacting with the tabstrip.
   if (!drag_controller_.get())
     ResizeLayoutTabs();
   else
     StartResizeLayoutTabsFromTouchTimer();
 }
 
@@ skipping 428 matching lines @@
   if (!adjust_layout_)
     return false;
 
 #if !defined(OS_CHROMEOS)
   if (ui::GetDisplayLayout() != ui::LAYOUT_TOUCH)
     return false;
 #endif
 
   return true;
 }