Add 'preserve trailing view size' capability into the SingleSplitView....

views/controls/single_split_view.cc

 // Copyright (c) 2006-2008 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 "views/controls/single_split_view.h"
 
 #if defined(OS_LINUX)
 #include <gdk/gdk.h>
 #endif
 
 #include "app/gfx/canvas.h"
 #include "skia/ext/skia_utils_win.h"
 #include "views/background.h"
 
 namespace views {
 
 // Size of the divider in pixels.
 static const int kDividerSize = 4;
 
 SingleSplitView::SingleSplitView(View* leading,
                                  View* trailing,
                                  Orientation orientation)
     : is_horizontal_(orientation == HORIZONTAL_SPLIT),
-      divider_offset_(-1) {
+      divider_offset_(-1),
+      resize_leading_on_bounds_change_(true) {
   AddChildView(leading);
   AddChildView(trailing);
 #if defined(OS_WIN)
   set_background(
       views::Background::CreateSolidBackground(
           skia::COLORREFToSkColor(GetSysColor(COLOR_3DFACE))));
 #endif
 }
 
+void SingleSplitView::DidChangeBounds(const gfx::Rect& previous,
+                                      const gfx::Rect& current) {
+  if (resize_leading_on_bounds_change_) {
+    if (is_horizontal_)
+      divider_offset_ += current.width() - previous.width();
+    else
+      divider_offset_ += current.height() - previous.height();
+
+    if (divider_offset_ < 0)
+      divider_offset_ = kDividerSize;
+  }
+  View::DidChangeBounds(previous, current);
+}
+
 void SingleSplitView::Layout() {
   if (GetChildViewCount() != 2)
     return;
 
   View* leading = GetChildViewAt(0);
   View* trailing = GetChildViewAt(1);
 
   if (!leading->IsVisible() && !trailing->IsVisible())
     return;
 
@@ skipping 115 matching lines @@
     divider_relative_offset =
         x - GetChildViewAt(UILayoutIsRightToLeft() ? 1 : 0)->width();
   } else {
     divider_relative_offset = y - GetChildViewAt(0)->height();
   }
   return (divider_relative_offset >= 0 &&
       divider_relative_offset < kDividerSize);
 }
 
 }  // namespace views