Fix task manager's default sizing.

chrome/browser/ui/views/task_manager_view.cc

 // Copyright 2015 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/task_manager_view.h"
 
 #include <stddef.h>
 
 #include "build/build_config.h"
 #include "chrome/browser/browser_process.h"
@@ skipping 129 matching lines @@
   // If |sorted_column_id| is the default value, it means to clear the sort.
   if (descriptor.sorted_column_id != TableSortDescriptor().sorted_column_id) {
     descriptor_list.emplace_back(descriptor.sorted_column_id,
                                  descriptor.is_ascending);
   }
 
   tab_table_->SetSortDescriptors(descriptor_list);
 }
 
 gfx::Size TaskManagerView::GetPreferredSize() const {
-  return gfx::Size(460, 270);
+  gfx::Size contents_size(tab_table_->GetPreferredSize().width(), 270);

[sky, 2016/09/15 02:52:13]

I think you should be able to ask tab_table_parent_ directly for the preferred
size and it should do the right thing. ScrollView considers the insets for the
bounded case, but not the !bounded case. Can you make ScrollView do the right
thing so that you only need set the height to 270 here? Seems like
TableView::CreateParent should return a ScrollView too so that you can call
ClipHeight directly to, but that's separate.

[Evan Stade, 2016/09/16 18:42:54]

ok, done. I was wary of touching anything in TableView or ScrollView because
it's complicated and I could be breaking something I'm not aware of, but this
patch seems to do the right thing.

I also tinkered with TableView::Layout because when there were enough tasks to
create a vertical scrollbar, that scrollbar was being placed on top of the
contents, obscuring part of the rightmost column (the contents weren't resized
to fit the space that was left over after the scrollbar was shown).

+  gfx::Insets scroll_view_border = tab_table_parent_->GetInsets();
+  contents_size.Enlarge(scroll_view_border.width(),
+                        scroll_view_border.height());
+  gfx::Insets border = GetInsets();
+  contents_size.Enlarge(border.width(), border.height());
+  return contents_size;
 }
 
 bool TaskManagerView::AcceleratorPressed(const ui::Accelerator& accelerator) {
   DCHECK_EQ(ui::VKEY_W, accelerator.key_code());
   DCHECK_EQ(ui::EF_CONTROL_DOWN, accelerator.modifiers());
   GetWidget()->Close();
   return true;
 }
 
 bool TaskManagerView::CanResize() const {
@@ skipping 196 matching lines @@
   if (!g_browser_process->local_state())
     return;
 
   const base::DictionaryValue* dictionary =
       g_browser_process->local_state()->GetDictionary(GetWindowName());
   if (dictionary)
     dictionary->GetBoolean("always_on_top", &is_always_on_top_);
 }
 
 }  // namespace task_manager