Make panel adjust bounds per preferred size change notification on Windows.

BUG=none
TEST=new browser test
Review URL: http://codereview.chromium.org/7537030

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@99880 0039d316-1c4b-4281-b951-d872f2087c98

32 files changed, 436 insertions, 45 deletions

diff --git a/chrome/browser/extensions/extension_host.h b/chrome/browser/extensions/extension_host.h
index 703daed..a0e100b 100644
--- a/chrome/browser/extensions/extension_host.h
+++ b/chrome/browser/extensions/extension_host.h
@@ -150,6 +150,7 @@ class ExtensionHost : public RenderViewHostDelegate,
   virtual void HandleMouseActivate() OVERRIDE;
   virtual void RunFileChooser(RenderViewHost* render_view_host,
                               const ViewHostMsg_RunFileChooser_Params& params);
+  virtual void UpdatePreferredSize(const gfx::Size& new_size);
 
   // RenderViewHostDelegate::View
   virtual void CreateNewWindow(
@@ -179,7 +180,6 @@ class ExtensionHost : public RenderViewHostDelegate,
   virtual void UpdateDragCursor(WebKit::WebDragOperation operation) OVERRIDE;
   virtual void GotFocus() OVERRIDE;
   virtual void TakeFocus(bool reverse) OVERRIDE;
-  virtual void UpdatePreferredSize(const gfx::Size& new_size) OVERRIDE;
 
   // NotificationObserver
   virtual void Observe(int type,
diff --git a/chrome/browser/notifications/balloon_host.h b/chrome/browser/notifications/balloon_host.h
index bc55201..921fbb0 100644
--- a/chrome/browser/notifications/balloon_host.h
+++ b/chrome/browser/notifications/balloon_host.h
@@ -63,6 +63,7 @@ class BalloonHost : public RenderViewHostDelegate,
   virtual void HandleMouseDown() OVERRIDE;
   virtual RendererPreferences GetRendererPrefs(
       content::BrowserContext* browser_context) const OVERRIDE;
+  virtual void UpdatePreferredSize(const gfx::Size& pref_size) OVERRIDE;
 
   // RenderViewHostDelegate::View methods. Only the ones for opening new
   // windows are currently implemented.
@@ -93,7 +94,6 @@ class BalloonHost : public RenderViewHostDelegate,
   virtual void UpdateDragCursor(WebKit::WebDragOperation operation) OVERRIDE {}
   virtual void GotFocus() OVERRIDE {}
   virtual void TakeFocus(bool reverse) OVERRIDE {}
-  virtual void UpdatePreferredSize(const gfx::Size& pref_size) OVERRIDE;
 
   // Enable Web UI. This has to be called before renderer is created.
   void EnableWebUI();
diff --git a/chrome/browser/tab_contents/background_contents.h b/chrome/browser/tab_contents/background_contents.h
index 950baae..afad19f 100644
--- a/chrome/browser/tab_contents/background_contents.h
+++ b/chrome/browser/tab_contents/background_contents.h
@@ -108,7 +108,6 @@ class BackgroundContents : public RenderViewHostDelegate,
   virtual void UpdateDragCursor(WebKit::WebDragOperation operation) {}
   virtual void GotFocus() {}
   virtual void TakeFocus(bool reverse) {}
-  virtual void UpdatePreferredSize(const gfx::Size& new_size) {}
 
   // NotificationObserver
   virtual void Observe(int type,
diff --git a/chrome/browser/tab_contents/tab_contents_view_gtk.cc b/chrome/browser/tab_contents/tab_contents_view_gtk.cc
index 92c737c..0ae84e5 100644
--- a/chrome/browser/tab_contents/tab_contents_view_gtk.cc
+++ b/chrome/browser/tab_contents/tab_contents_view_gtk.cc
@@ -247,9 +247,6 @@ void TabContentsViewGtk::RestoreFocus() {
     SetInitialFocus();
 }
 
-void TabContentsViewGtk::UpdatePreferredSize(const gfx::Size& pref_size) {
-}
-
 bool TabContentsViewGtk::IsDoingDrag() const {
   return false;
 }
diff --git a/chrome/browser/tab_contents/tab_contents_view_gtk.h b/chrome/browser/tab_contents/tab_contents_view_gtk.h
index 5e5bd0a..b21171f 100644
--- a/chrome/browser/tab_contents/tab_contents_view_gtk.h
+++ b/chrome/browser/tab_contents/tab_contents_view_gtk.h
@@ -62,7 +62,6 @@ class TabContentsViewGtk : public TabContentsView,
   virtual void SetInitialFocus() OVERRIDE;
   virtual void StoreFocus() OVERRIDE;
   virtual void RestoreFocus() OVERRIDE;
-  virtual void UpdatePreferredSize(const gfx::Size& pref_size) OVERRIDE;
   virtual bool IsDoingDrag() const OVERRIDE;
   virtual void CancelDragAndCloseTab() OVERRIDE;
   virtual bool IsEventTracking() const OVERRIDE;
diff --git a/chrome/browser/tab_contents/tab_contents_view_mac.h b/chrome/browser/tab_contents/tab_contents_view_mac.h
index 0ece02e..809bf23 100644
--- a/chrome/browser/tab_contents/tab_contents_view_mac.h
+++ b/chrome/browser/tab_contents/tab_contents_view_mac.h
@@ -73,7 +73,6 @@ class TabContentsViewMac : public TabContentsView,
   virtual void SetInitialFocus() OVERRIDE;
   virtual void StoreFocus() OVERRIDE;
   virtual void RestoreFocus() OVERRIDE;
-  virtual void UpdatePreferredSize(const gfx::Size& pref_size) OVERRIDE;
   virtual bool IsDoingDrag() const OVERRIDE;
   virtual void CancelDragAndCloseTab() OVERRIDE;
   virtual bool IsEventTracking() const OVERRIDE;
diff --git a/chrome/browser/tab_contents/tab_contents_view_mac.mm b/chrome/browser/tab_contents/tab_contents_view_mac.mm
index 1c315b0..b6bafea 100644
--- a/chrome/browser/tab_contents/tab_contents_view_mac.mm
+++ b/chrome/browser/tab_contents/tab_contents_view_mac.mm
@@ -234,10 +234,6 @@ void TabContentsViewMac::RestoreFocus() {
   focus_tracker_.reset(nil);
 }
 
-void TabContentsViewMac::UpdatePreferredSize(const gfx::Size& pref_size) {
-  preferred_width_ = pref_size.width();
-}
-
 bool TabContentsViewMac::IsDoingDrag() const {
   return false;
 }
diff --git a/chrome/browser/ui/browser.cc b/chrome/browser/ui/browser.cc
index d96ca0c..e92d6c7 100644
--- a/chrome/browser/ui/browser.cc
+++ b/chrome/browser/ui/browser.cc
@@ -3438,11 +3438,6 @@ void Browser::AddNewContents(TabContents* source,
   params.window_action = browser::NavigateParams::SHOW_WINDOW;
   params.user_gesture = user_gesture;
   browser::Navigate(&params);
-
-  NotificationService::current()->Notify(
-    content::NOTIFICATION_TAB_ADDED,
-    Source<TabContentsDelegate>(this),
-    Details<TabContents>(new_contents));
 }
 
 void Browser::ActivateContents(TabContents* contents) {
@@ -3881,6 +3876,11 @@ void Browser::ExitTabbedFullscreenModeIfNecessary() {
     NotifyTabOfFullscreenExitIfNecessary();
 }
 
+void Browser::UpdatePreferredSize(TabContents* source,
+                                  const gfx::Size& pref_size) {
+  window_->UpdatePreferredSize(source, pref_size);
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 // Browser, TabContentsWrapperDelegate implementation:
 
diff --git a/chrome/browser/ui/browser.h b/chrome/browser/ui/browser.h
index fdd1083..00f6440 100644
--- a/chrome/browser/ui/browser.h
+++ b/chrome/browser/ui/browser.h
@@ -981,6 +981,8 @@ class Browser : public TabHandlerDelegate,
                                  const string16& type,
                                  const string16& data,
                                  int intent_id) OVERRIDE;
+  virtual void UpdatePreferredSize(TabContents* source,
+                                   const gfx::Size& pref_size) OVERRIDE;
 
   virtual void FindReply(TabContents* tab,
                          int request_id,
diff --git a/chrome/browser/ui/browser_navigator.cc b/chrome/browser/ui/browser_navigator.cc
index f597016..a62496b 100644
--- a/chrome/browser/ui/browser_navigator.cc
+++ b/chrome/browser/ui/browser_navigator.cc
@@ -533,6 +533,13 @@ void Navigate(NavigateParams* params) {
     if (params->source_contents != params->target_contents)
       params->browser->ActivateTabAt(singleton_index, user_initiated);
   }
+
+  if (params->disposition != CURRENT_TAB) {
+    NotificationService::current()->Notify(
+        content::NOTIFICATION_TAB_ADDED,
+        Source<TabContentsDelegate>(params->browser),
+        Details<TabContents>(params->target_contents->tab_contents()));
+  }
 }
 
 // Returns the index of an existing singleton tab in |params->browser| matching
diff --git a/chrome/browser/ui/browser_window.h b/chrome/browser/ui/browser_window.h
index 51e96f9..8da015c 100644
--- a/chrome/browser/ui/browser_window.h
+++ b/chrome/browser/ui/browser_window.h
@@ -33,6 +33,7 @@ struct NativeWebKeyboardEvent;
 
 namespace gfx {
 class Rect;
+class Size;
 }
 
 class Extension;
@@ -344,6 +345,13 @@ class BrowserWindow {
   virtual void ShowKeyboardOverlay(gfx::NativeWindow owning_window) = 0;
 #endif
 
+  // Invoked when the preferred size of the contents in current tab has been
+  // changed. We might choose to update the window size to accomodate this
+  // change.
+  // Note that this won't be fired if we change tabs.
+  virtual void UpdatePreferredSize(TabContents* tab_contents,
+                                   const gfx::Size& pref_size) {}
+
   // Construct a BrowserWindow implementation for the specified |browser|.
   static BrowserWindow* CreateBrowserWindow(Browser* browser);
 
diff --git a/chrome/browser/ui/panels/base_panel_browser_test.cc b/chrome/browser/ui/panels/base_panel_browser_test.cc
index b0a4c05..4015c52 100644
--- a/chrome/browser/ui/panels/base_panel_browser_test.cc
+++ b/chrome/browser/ui/panels/base_panel_browser_test.cc
@@ -13,7 +13,9 @@
 #include "chrome/browser/ui/panels/panel_manager.h"
 #include "chrome/browser/ui/tab_contents/tab_contents_wrapper.h"
 #include "chrome/common/chrome_switches.h"
+#include "chrome/test/base/ui_test_utils.h"
 #include "content/browser/tab_contents/test_tab_contents.h"
+#include "content/common/url_constants.h"
 
 #if defined(OS_MACOSX)
 #include "chrome/browser/ui/cocoa/find_bar/find_bar_bridge.h"
@@ -158,6 +160,7 @@ BasePanelBrowserTest::~BasePanelBrowserTest() {
 }
 
 void BasePanelBrowserTest::SetUpCommandLine(CommandLine* command_line) {
+  EnableDOMAutomation();
   command_line->AppendSwitch(switches::kEnablePanels);
 }
 
@@ -171,6 +174,7 @@ void BasePanelBrowserTest::SetUpOnMainThread() {
       panel_manager);
   panel_manager->set_auto_hiding_desktop_bar(mock_auto_hiding_desktop_bar_);
   panel_manager->SetWorkAreaForTesting(testing_work_area_);
+  panel_manager->enable_auto_sizing(false);
 }
 
 Panel* BasePanelBrowserTest::CreatePanelWithParams(
@@ -189,9 +193,16 @@ Panel* BasePanelBrowserTest::CreatePanelWithParams(
                                                  browser()->profile());
   EXPECT_TRUE(panel_browser->is_type_panel());
 
-  TabContentsWrapper* tab_contents =
-      new TabContentsWrapper(new TestTabContents(browser()->profile(), NULL));
-  panel_browser->AddTab(tab_contents, PageTransition::LINK);
+  if (params.url.is_empty()) {
+    TabContentsWrapper* tab_contents =
+        new TabContentsWrapper(new TestTabContents(browser()->profile(), NULL));
+    panel_browser->AddTab(tab_contents, PageTransition::LINK);
+  } else {
+    panel_browser->AddSelectedTabWithURL(params.url,
+                                         PageTransition::START_PAGE);
+    ui_test_utils::WaitForNavigation(
+        &panel_browser->GetSelectedTabContents()->controller());
+  }
 
   Panel* panel = static_cast<Panel*>(panel_browser->window());
   if (params.show_flag == SHOW_AS_ACTIVE)
diff --git a/chrome/browser/ui/panels/base_panel_browser_test.h b/chrome/browser/ui/panels/base_panel_browser_test.h
index 2f08401..685acc1 100644
--- a/chrome/browser/ui/panels/base_panel_browser_test.h
+++ b/chrome/browser/ui/panels/base_panel_browser_test.h
@@ -42,6 +42,7 @@ class BasePanelBrowserTest : public InProcessBrowserTest {
     std::string name;
     gfx::Rect bounds;
     ShowFlag show_flag;
+    GURL url;
 
     CreatePanelParams(const std::string& name,
                       const gfx::Rect& bounds,
diff --git a/chrome/browser/ui/panels/native_panel.h b/chrome/browser/ui/panels/native_panel.h
index 2a4fdb1..8aa419d 100644
--- a/chrome/browser/ui/panels/native_panel.h
+++ b/chrome/browser/ui/panels/native_panel.h
@@ -67,6 +67,15 @@ class NativePanel {
 
   virtual Browser* GetPanelBrowser() const = 0;
   virtual void DestroyPanelBrowser() = 0;
+
+  // Returns the extent of the non-client area, that is, the window size minus
+  // the size of the client area.
+  virtual gfx::Size GetNonClientAreaExtent() const = 0;
+
+  // Gets or sets the restored height, which is the full height of the panel
+  // when it is expanded.
+  virtual int GetRestoredHeight() const = 0;
+  virtual void SetRestoredHeight(int height) = 0;
 };
 
 // A NativePanel utility interface used for accessing elements of the
diff --git a/chrome/browser/ui/panels/panel.cc b/chrome/browser/ui/panels/panel.cc
index b598ab9..7195e30 100644
--- a/chrome/browser/ui/panels/panel.cc
+++ b/chrome/browser/ui/panels/panel.cc
@@ -8,12 +8,16 @@
 #include "chrome/browser/extensions/extension_prefs.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/profiles/profile.h"
+#include "content/browser/renderer_host/render_view_host.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/panels/native_panel.h"
 #include "chrome/browser/ui/panels/panel_manager.h"
 #include "chrome/browser/ui/window_sizer.h"
 #include "chrome/browser/web_applications/web_app.h"
 #include "chrome/common/extensions/extension.h"
+#include "content/browser/tab_contents/tab_contents.h"
+#include "content/common/content_notification_types.h"
+#include "content/common/view_messages.h"
 #include "ui/gfx/rect.h"
 
 // static
@@ -27,9 +31,15 @@ const Extension* Panel::GetExtension(Browser* browser) {
 }
 
 Panel::Panel(Browser* browser, const gfx::Rect& bounds)
-    : native_panel_(NULL),
+    : min_size_(bounds.size()),
+      max_size_(bounds.size()),
+      native_panel_(NULL),
       expansion_state_(EXPANDED) {
   native_panel_ = CreateNativePanel(browser, this, bounds);
+
+  registrar_.Add(this,
+                 content::NOTIFICATION_TAB_ADDED,
+                 Source<TabContentsDelegate>(browser));
 }
 
 Panel::~Panel() {
@@ -44,6 +54,18 @@ void Panel::SetPanelBounds(const gfx::Rect& bounds) {
   native_panel_->SetPanelBounds(bounds);
 }
 
+void Panel::SetMaxSize(const gfx::Size& max_size) {
+  if (max_size_ == max_size)
+    return;
+  max_size_ = max_size;
+
+  // Note: |render_view_host| might be NULL if the tab has not been created.
+  // If so, we will do it when NOTIFICATION_TAB_ADDED is received.
+  RenderViewHost* render_view_host = GetRenderViewHost();
+  if (render_view_host)
+    RequestRenderViewHostToDisableScrollbars(render_view_host);
+}
+
 void Panel::SetExpansionState(ExpansionState new_expansion_state) {
   if (expansion_state_ == new_expansion_state)
     return;
@@ -75,6 +97,14 @@ bool Panel::IsDrawingAttention() const {
   return native_panel_->IsDrawingAttention();
 }
 
+int Panel::GetRestoredHeight() const {
+  return native_panel_->GetRestoredHeight();
+}
+
+void Panel::SetRestoredHeight(int height) {
+  native_panel_->SetRestoredHeight(height);
+}
+
 void Panel::Show() {
   native_panel_->ShowPanel();
 }
@@ -445,6 +475,52 @@ void Panel::ShowKeyboardOverlay(gfx::NativeWindow owning_window) {
 }
 #endif
 
+void Panel::UpdatePreferredSize(TabContents* tab_contents,
+                                const gfx::Size& pref_size) {
+  gfx::Size non_client_size = native_panel_->GetNonClientAreaExtent();
+  return manager()->OnPreferredWindowSizeChanged(this,
+      gfx::Size(pref_size.width() + non_client_size.width(),
+                pref_size.height() + non_client_size.height()));
+}
+
+void Panel::Observe(int type,
+                    const NotificationSource& source,
+                    const NotificationDetails& details) {
+  switch (type) {
+    case content::NOTIFICATION_TAB_ADDED:
+    case content::NOTIFICATION_TAB_CONTENTS_SWAPPED: {
+      RenderViewHost* render_view_host = GetRenderViewHost();
+      DCHECK(render_view_host);
+      render_view_host->Send(new ViewMsg_EnablePreferredSizeChangedMode(
+          render_view_host->routing_id(),
+          kPreferredSizeWidth | kPreferredSizeHeightThisIsSlow));
+      RequestRenderViewHostToDisableScrollbars(render_view_host);
+      break;
+    }
+    default:
+      NOTREACHED() << "Got a notification we didn't register for!";
+      break;
+  }
+}
+
+RenderViewHost* Panel::GetRenderViewHost() const {
+  TabContents* tab_contents = browser()->GetSelectedTabContents();
+  if (!tab_contents)
+    return NULL;
+  return tab_contents->render_view_host();
+}
+
+void Panel::RequestRenderViewHostToDisableScrollbars(
+    RenderViewHost* render_view_host) {
+  DCHECK(render_view_host);
+
+  gfx::Size non_client_size = native_panel_->GetNonClientAreaExtent();
+  render_view_host->Send(new ViewMsg_DisableScrollbarsForSmallWindows(
+      render_view_host->routing_id(),
+      gfx::Size(max_size_.width() - non_client_size.width(),
+                max_size_.height() - non_client_size.height())));
+}
+
 Browser* Panel::browser() const {
   return native_panel_->GetPanelBrowser();
 }
diff --git a/chrome/browser/ui/panels/panel.h b/chrome/browser/ui/panels/panel.h
index 81b5548f2..bdf3c2d 100644
--- a/chrome/browser/ui/panels/panel.h
+++ b/chrome/browser/ui/panels/panel.h
@@ -9,10 +9,13 @@
 #include "chrome/browser/ui/browser_window.h"
 
 #include "base/memory/scoped_ptr.h"
+#include "content/common/notification_observer.h"
+#include "content/common/notification_registrar.h"
 #include "ui/gfx/rect.h"
 
 class NativePanel;
 class PanelManager;
+class RenderViewHost;
 
 // A platform independent implementation of BrowserWindow for Panels.  This
 // class would get the first crack at all the BrowserWindow calls for Panels and
@@ -24,7 +27,7 @@ class PanelManager;
 //   Panel size is restricted to certain limits.
 // - Invoke an appropriate PanelManager function to do stuff that might affect
 //   other Panels.  For example deleting a panel would rearrange other panels.
-class Panel : public BrowserWindow {
+class Panel : public BrowserWindow, public NotificationObserver {
  public:
   enum ExpansionState {
    // The panel is fully expanded with both title-bar and the client-area.
@@ -46,6 +49,11 @@ class Panel : public BrowserWindow {
 
   bool IsDrawingAttention() const;
 
+  // Gets or sets the restored height, which is the full height of the panel
+  // when it is expanded.
+  int GetRestoredHeight() const;
+  void SetRestoredHeight(int height);
+
   // BrowserWindow overrides.
   virtual void Show() OVERRIDE;
   virtual void ShowInactive() OVERRIDE;
@@ -146,6 +154,13 @@ class Panel : public BrowserWindow {
 #if defined(OS_CHROMEOS)
   virtual void ShowKeyboardOverlay(gfx::NativeWindow owning_window) OVERRIDE;
 #endif
+  virtual void UpdatePreferredSize(TabContents* tab_contents,
+                                   const gfx::Size& pref_size) OVERRIDE;
+
+  // NotificationObserver overrides.
+  virtual void Observe(int type,
+                       const NotificationSource& source,
+                       const NotificationDetails& details) OVERRIDE;
 
   // Construct a native panel BrowserWindow implementation for the specified
   // |browser|.
@@ -157,12 +172,11 @@ class Panel : public BrowserWindow {
   // Returns NULL if it cannot be found.
   static const Extension* GetExtension(Browser* browser);
 
-#ifdef UNIT_TEST
   NativePanel* native_panel() { return native_panel_; }
-#endif
-
   Browser* browser() const;
   ExpansionState expansion_state() const { return expansion_state_; }
+  const gfx::Size& min_size() const { return min_size_; }
+  const gfx::Size& max_size() const { return max_size_; }
 
  protected:
   virtual void DestroyBrowser() OVERRIDE;
@@ -179,12 +193,32 @@ class Panel : public BrowserWindow {
   //   not allowed for Panel.
   void SetPanelBounds(const gfx::Rect& bounds);
 
+  // Updates the maximum size.
+  void SetMaxSize(const gfx::Size& max_size);
+
+  // NULL might be returned if the tab has not been added.
+  RenderViewHost* GetRenderViewHost() const;
+
+  // Requests RenderViewHost not to show the scrollbars till |max_size_| since
+  // the panel can grow to |max_size_|.
+  void RequestRenderViewHostToDisableScrollbars(
+      RenderViewHost* render_view_host);
+
+  // This is the minimum size that the panel can shrink to.
+  gfx::Size min_size_;
+
+  // This is the size beyond which the panel is not going to grow to accomodate
+  // the growing content and WebKit would add the scrollbars in such case.
+  gfx::Size max_size_;
+
   // Platform specifc implementation for panels.  It'd be one of
   // PanelBrowserWindowGtk/PanelBrowserView/PanelBrowserWindowCocoa.
   NativePanel* native_panel_;  // Weak, owns us.
 
   ExpansionState expansion_state_;
 
+  NotificationRegistrar registrar_;
+
   DISALLOW_COPY_AND_ASSIGN(Panel);
 };
 
diff --git a/chrome/browser/ui/panels/panel_browser_frame_view.cc b/chrome/browser/ui/panels/panel_browser_frame_view.cc
index ef907fd..3acb5f6 100644
--- a/chrome/browser/ui/panels/panel_browser_frame_view.cc
+++ b/chrome/browser/ui/panels/panel_browser_frame_view.cc
@@ -560,6 +560,11 @@ int PanelBrowserFrameView::MinimizedPanelHeight() {
   return kMinimizedPanelHeight;
 }
 
+gfx::Size PanelBrowserFrameView::NonClientAreaSize() const {
+  return gfx::Size(NonClientBorderThickness() * 2,
+                   NonClientTopBorderHeight() + NonClientBorderThickness());
+}
+
 SkColor PanelBrowserFrameView::GetTitleColor(PaintState paint_state) const {
   switch (paint_state) {
     case PAINT_AS_INACTIVE:
diff --git a/chrome/browser/ui/panels/panel_browser_frame_view.h b/chrome/browser/ui/panels/panel_browser_frame_view.h
index fa98d54..c454a8b 100644
--- a/chrome/browser/ui/panels/panel_browser_frame_view.h
+++ b/chrome/browser/ui/panels/panel_browser_frame_view.h
@@ -47,6 +47,10 @@ class PanelBrowserFrameView : public BrowserNonClientFrameView,
   // Returns the height of the panel in minimized state.
   static int MinimizedPanelHeight();
 
+  // Returns the size of the non-client area, that is, the window size minus
+  // the size of the client area.
+  gfx::Size NonClientAreaSize() const;
+
  protected:
   // Overridden from BrowserNonClientFrameView:
   virtual gfx::Rect GetBoundsForTabStrip(views::View* tabstrip) const OVERRIDE;
diff --git a/chrome/browser/ui/panels/panel_browser_view.cc b/chrome/browser/ui/panels/panel_browser_view.cc
index 470e8fb..f7cada5 100644
--- a/chrome/browser/ui/panels/panel_browser_view.cc
+++ b/chrome/browser/ui/panels/panel_browser_view.cc
@@ -37,7 +37,7 @@ PanelBrowserView::PanelBrowserView(Browser* browser, Panel* panel,
   : BrowserView(browser),
     panel_(panel),
     bounds_(bounds),
-    original_height_(bounds.height()),
+    restored_height_(bounds.height()),
     closed_(false),
     focused_(false),
     mouse_pressed_(false),
@@ -82,8 +82,13 @@ bool PanelBrowserView::CanMaximize() const {
 }
 
 void PanelBrowserView::SetBounds(const gfx::Rect& bounds) {
+  if (bounds_ == bounds)
+    return;
   bounds_ = bounds;
 
+  if (panel_->expansion_state() == Panel::EXPANDED)
+    restored_height_ = bounds.height();
+
   // No animation if the panel is being dragged.
   if (mouse_dragging_) {
     ::BrowserView::SetBounds(bounds);
@@ -194,7 +199,7 @@ void PanelBrowserView::OnPanelExpansionStateChanged(
   int height;
   switch (expansion_state) {
     case Panel::EXPANDED:
-      height = original_height_;
+      height = restored_height_;
       break;
     case Panel::TITLE_ONLY:
       height = GetFrameView()->NonClientTopBorderHeight();
@@ -210,7 +215,7 @@ void PanelBrowserView::OnPanelExpansionStateChanged(
       break;
     default:
       NOTREACHED();
-      height = original_height_;
+      height = restored_height_;
       break;
   }
 
@@ -318,6 +323,18 @@ void PanelBrowserView::HandlePanelKeyboardEvent(
   HandleKeyboardEvent(event);
 }
 
+gfx::Size PanelBrowserView::GetNonClientAreaExtent() const {
+  return GetFrameView()->NonClientAreaSize();
+}
+
+int PanelBrowserView::GetRestoredHeight() const {
+  return restored_height_;
+}
+
+void PanelBrowserView::SetRestoredHeight(int height) {
+  restored_height_ = height;
+}
+
 Browser* PanelBrowserView::GetPanelBrowser() const {
   return browser();
 }
diff --git a/chrome/browser/ui/panels/panel_browser_view.h b/chrome/browser/ui/panels/panel_browser_view.h
index c855fd0..d42299c 100644
--- a/chrome/browser/ui/panels/panel_browser_view.h
+++ b/chrome/browser/ui/panels/panel_browser_view.h
@@ -96,6 +96,9 @@ class PanelBrowserView : public BrowserView,
       bool* is_keyboard_shortcut) OVERRIDE;
   virtual void HandlePanelKeyboardEvent(
       const NativeWebKeyboardEvent& event) OVERRIDE;
+  virtual gfx::Size GetNonClientAreaExtent() const OVERRIDE;
+  virtual int GetRestoredHeight() const OVERRIDE;
+  virtual void SetRestoredHeight(int height) OVERRIDE;
   virtual Browser* GetPanelBrowser() const OVERRIDE;
   virtual void DestroyPanelBrowser() OVERRIDE;
 
@@ -109,9 +112,9 @@ class PanelBrowserView : public BrowserView,
   scoped_ptr<Panel> panel_;
   gfx::Rect bounds_;
 
-  // Stores the original height of the panel so we can restore it after it's
+  // Stores the full height of the panel so we can restore it after it's
   // been minimized.
-  int original_height_;
+  int restored_height_;
 
   // Is the panel being closed? Do not use it when it is closed.
   bool closed_;
diff --git a/chrome/browser/ui/panels/panel_browser_view_browsertest.cc b/chrome/browser/ui/panels/panel_browser_view_browsertest.cc
index 834398e..d48f107 100644
--- a/chrome/browser/ui/panels/panel_browser_view_browsertest.cc
+++ b/chrome/browser/ui/panels/panel_browser_view_browsertest.cc
@@ -13,10 +13,13 @@
 #include "chrome/browser/ui/panels/panel_browser_view.h"
 #include "chrome/browser/ui/panels/panel_manager.h"
 #include "chrome/browser/ui/panels/panel_mouse_watcher_win.h"
+#include "chrome/browser/ui/tab_contents/tab_contents_wrapper.h"
 #include "chrome/browser/web_applications/web_app.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/extensions/extension.h"
+#include "chrome/test/base/ui_test_utils.h"
 #include "grit/generated_resources.h"
+#include "net/base/net_util.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/base/animation/slide_animation.h"
@@ -27,6 +30,9 @@
 #include "views/controls/link.h"
 #include "views/controls/textfield/textfield.h"
 
+const FilePath::CharType* kUpdateSizeTestFile =
+    FILE_PATH_LITERAL("update-preferred-size.html");
+
 class PanelBrowserViewTest : public BasePanelBrowserTest {
  public:
   PanelBrowserViewTest() : BasePanelBrowserTest() { }
@@ -386,6 +392,57 @@ class PanelBrowserViewTest : public BasePanelBrowserTest {
 
     panel->Close();
   }
+
+  void TestUpdatePreferredSize() {
+    PanelManager::GetInstance()->enable_auto_sizing(true);
+
+    // Create a test panel with tab contents loaded.
+    CreatePanelParams params("PanelTest1", gfx::Rect(0, 0, 100, 100),
+                             SHOW_AS_ACTIVE);
+    params.url = GURL(chrome::kAboutBlankURL);
+    Panel* panel = CreatePanelWithParams(params);
+
+    // Load the test page.
+    ui_test_utils::NavigateToURL(panel->browser(),
+        ui_test_utils::GetTestUrl(FilePath(FilePath::kCurrentDirectory),
+                                  FilePath(kUpdateSizeTestFile)));
+    gfx::Rect initial_bounds = panel->GetBounds();
+    EXPECT_EQ(100, initial_bounds.width());
+    EXPECT_EQ(100, initial_bounds.height());
+
+    // Expand the test page.
+    EXPECT_TRUE(ui_test_utils::ExecuteJavaScript(
+        panel->browser()->GetSelectedTabContents()->render_view_host(),
+        std::wstring(),
+        L"changeSize(50);"));
+
+    // Wait till the bounds get changed.
+    gfx::Rect bounds_on_grow;
+    while ((bounds_on_grow = panel->GetBounds()) == initial_bounds) {
+      MessageLoop::current()->PostTask(FROM_HERE, new MessageLoop::QuitTask());
+      MessageLoop::current()->RunAllPending();
+    }
+    EXPECT_GT(bounds_on_grow.width(), initial_bounds.width());
+    EXPECT_EQ(bounds_on_grow.height(), initial_bounds.height());
+
+    // Shrink the test page.
+    EXPECT_TRUE(ui_test_utils::ExecuteJavaScript(
+        panel->browser()->GetSelectedTabContents()->render_view_host(),
+        std::wstring(),
+        L"changeSize(-30);"));
+
+    // Wait till the bounds get changed.
+    gfx::Rect bounds_on_shrink;
+    while ((bounds_on_shrink = panel->GetBounds()) == bounds_on_grow) {
+      MessageLoop::current()->PostTask(FROM_HERE, new MessageLoop::QuitTask());
+      MessageLoop::current()->RunAllPending();
+    }
+    EXPECT_LT(bounds_on_shrink.width(), bounds_on_grow.width());
+    EXPECT_GT(bounds_on_shrink.width(), initial_bounds.width());
+    EXPECT_EQ(bounds_on_shrink.height(), initial_bounds.height());
+
+    panel->Close();
+  }
 };
 
 // Panel is not supported for Linux view yet.
@@ -535,4 +592,8 @@ IN_PROC_BROWSER_TEST_F(PanelBrowserViewTest, DISABLED_DrawAttention) {
 IN_PROC_BROWSER_TEST_F(PanelBrowserViewTest, ChangeAutoHideTaskBarThickness) {
   TestChangeAutoHideTaskBarThickness();
 }
+
+IN_PROC_BROWSER_TEST_F(PanelBrowserViewTest, UpdatePreferredSize) {
+  TestUpdatePreferredSize();
+}
 #endif
diff --git a/chrome/browser/ui/panels/panel_browser_window_cocoa.h b/chrome/browser/ui/panels/panel_browser_window_cocoa.h
index 73620e0d..6c33f92 100644
--- a/chrome/browser/ui/panels/panel_browser_window_cocoa.h
+++ b/chrome/browser/ui/panels/panel_browser_window_cocoa.h
@@ -52,6 +52,9 @@ class PanelBrowserWindowCocoa : public NativePanel {
       const NativeWebKeyboardEvent& event) OVERRIDE;
   virtual Browser* GetPanelBrowser() const OVERRIDE;
   virtual void DestroyPanelBrowser() OVERRIDE;
+  virtual gfx::Size GetNonClientAreaExtent() const OVERRIDE;
+  virtual int GetRestoredHeight() const OVERRIDE;
+  virtual void SetRestoredHeight(int height) OVERRIDE;
 
   Panel* panel() { return panel_.get(); }
   Browser* browser() const { return browser_.get(); }
diff --git a/chrome/browser/ui/panels/panel_browser_window_cocoa.mm b/chrome/browser/ui/panels/panel_browser_window_cocoa.mm
index facaf2d..0e97848 100644
--- a/chrome/browser/ui/panels/panel_browser_window_cocoa.mm
+++ b/chrome/browser/ui/panels/panel_browser_window_cocoa.mm
@@ -197,6 +197,20 @@ void PanelBrowserWindowCocoa::didCloseNativeWindow() {
   panel_->manager()->Remove(panel_.get());
   controller_ = NULL;
 }
+gfx::Size PanelBrowserWindowCocoa::GetNonClientAreaExtent() const {
+  NOTIMPLEMENTED();
+  return gfx::Size();
+}
+
+int PanelBrowserWindowCocoa::GetRestoredHeight() const {
+  NOTIMPLEMENTED();
+  return 0;
+}
+
+void PanelBrowserWindowCocoa::SetRestoredHeight(int height) {
+  NOTIMPLEMENTED();
+}
+
 // NativePanelTesting implementation.
 
 // static
diff --git a/chrome/browser/ui/panels/panel_browser_window_gtk.cc b/chrome/browser/ui/panels/panel_browser_window_gtk.cc
index 4f6eb97..f80ff30 100644
--- a/chrome/browser/ui/panels/panel_browser_window_gtk.cc
+++ b/chrome/browser/ui/panels/panel_browser_window_gtk.cc
@@ -192,6 +192,20 @@ void PanelBrowserWindowGtk::DestroyPanelBrowser() {
   DestroyBrowser();
 }
 
+gfx::Size PanelBrowserWindowGtk::GetNonClientAreaExtent() const {
+  NOTIMPLEMENTED();
+  return gfx::Size();
+}
+
+int PanelBrowserWindowGtk::GetRestoredHeight() const {
+  NOTIMPLEMENTED();
+  return 0;
+}
+
+void PanelBrowserWindowGtk::SetRestoredHeight(int height) {
+  NOTIMPLEMENTED();
+}
+
 void PanelBrowserWindowGtk::SetBoundsImpl() {
   gtk_window_move(window_, bounds_.x(), bounds_.y());
   gtk_window_resize(window(), bounds_.width(), bounds_.height());
diff --git a/chrome/browser/ui/panels/panel_browser_window_gtk.h b/chrome/browser/ui/panels/panel_browser_window_gtk.h
index c13e2d7..53c90fb 100644
--- a/chrome/browser/ui/panels/panel_browser_window_gtk.h
+++ b/chrome/browser/ui/panels/panel_browser_window_gtk.h
@@ -64,6 +64,9 @@ class PanelBrowserWindowGtk : public BrowserWindowGtk,
       const NativeWebKeyboardEvent& event) OVERRIDE;
   virtual Browser* GetPanelBrowser() const OVERRIDE;
   virtual void DestroyPanelBrowser() OVERRIDE;
+  virtual gfx::Size GetNonClientAreaExtent() const OVERRIDE;
+  virtual int GetRestoredHeight() const OVERRIDE;
+  virtual void SetRestoredHeight(int height) OVERRIDE;
 
  private:
   void SetBoundsImpl();
diff --git a/chrome/browser/ui/panels/panel_manager.cc b/chrome/browser/ui/panels/panel_manager.cc
index 20c0198..ee0d5f9 100644
--- a/chrome/browser/ui/panels/panel_manager.cc
+++ b/chrome/browser/ui/panels/panel_manager.cc
@@ -17,8 +17,10 @@ namespace {
 const size_t kInvalidPanelIndex = static_cast<size_t>(-1);
 
 // Minimum width and height of a panel.
-const int kPanelMinWidthPixels = 64;
-const int kPanelMinHeightPixels = 24;
+// Note: The minimum size of a widget (see widget.cc) is fixed to 100x100.
+// TODO(jianli): Need to fix this to support smaller panel.
+const int kPanelMinWidthPixels = 100;
+const int kPanelMinHeightPixels = 100;
 
 // Default width and height of a panel.
 const int kPanelDefaultWidthPixels = 240;
@@ -50,7 +52,8 @@ PanelManager::PanelManager()
     : dragging_panel_index_(kInvalidPanelIndex),
       dragging_panel_original_x_(0),
       delayed_titlebar_action_(NO_ACTION),
-      ALLOW_THIS_IN_INITIALIZER_LIST(method_factory_(this)) {
+      ALLOW_THIS_IN_INITIALIZER_LIST(method_factory_(this)),
+      auto_sizing_enabled_(true) {
   auto_hiding_desktop_bar_ = AutoHidingDesktopBar::Create(this);
   OnDisplayChanged();
 }
@@ -107,10 +110,8 @@ Panel* PanelManager::CreatePanel(Browser* browser) {
     height = kPanelDefaultHeightPixels;
   }
 
-  int max_panel_width =
-      static_cast<int>(adjusted_work_area_.width() * kPanelMaxWidthFactor);
-  int max_panel_height =
-      static_cast<int>(adjusted_work_area_.height() * kPanelMaxHeightFactor);
+  int max_panel_width = GetMaxPanelWidth();
+  int max_panel_height = GetMaxPanelHeight();
 
   if (width < kPanelMinWidthPixels)
     width = kPanelMinWidthPixels;
@@ -139,9 +140,19 @@ Panel* PanelManager::CreatePanel(Browser* browser) {
   Panel* panel = new Panel(browser, gfx::Rect(x, y, width, height));
   panels_.push_back(panel);
 
+  UpdateMaxSizeForAllPanels();
+
   return panel;
 }
 
+int PanelManager::GetMaxPanelWidth() const {
+  return static_cast<int>(adjusted_work_area_.width() * kPanelMaxWidthFactor);
+}
+
+int PanelManager::GetMaxPanelHeight() const {
+  return static_cast<int>(adjusted_work_area_.height() * kPanelMaxHeightFactor);
+}
+
 int PanelManager::GetRightMostAvaialblePosition() const {
   return panels_.empty() ? adjusted_work_area_.right() :
       (panels_.back()->GetBounds().x() - kPanelsHorizontalSpacing);
@@ -303,6 +314,74 @@ void PanelManager::EndDragging(bool cancelled) {
   DelayedRemove();
 }
 
+void PanelManager::OnPreferredWindowSizeChanged(
+    Panel* panel, const gfx::Size& preferred_window_size) {
+  if (!auto_sizing_enabled_)
+    return;
+
+  gfx::Rect bounds = panel->GetBounds();
+  int restored_height = panel->GetRestoredHeight();
+
+  // The panel width:
+  // * cannot grow or shrink to go beyond [min_width, max_width]
+  // * cannot grow to take more than the available space and go beyond the left
+  //   of the work area.
+  int new_width = preferred_window_size.width();
+  if (new_width > panel->max_size().width())
+    new_width = panel->max_size().width();
+  if (new_width < panel->min_size().width())
+    new_width = panel->min_size().width();
+
+  int right_most_available_position = GetRightMostAvaialblePosition();
+  if (new_width - bounds.width() > right_most_available_position)
+    new_width = bounds.width() + right_most_available_position;
+
+  if (new_width != bounds.width()) {
+    int delta = bounds.width() - new_width;
+    bounds.set_x(bounds.x() + delta);
+    bounds.set_width(new_width);
+
+    // Reposition all the panels on the left.
+    int panel_index = -1;
+    for (int i = 0; i < static_cast<int>(panels_.size()); ++i) {
+      if (panels_[i] == panel) {
+        panel_index = i;
+        break;
+      }
+    }
+    DCHECK(panel_index >= 0);
+    for (int i = static_cast<int>(panels_.size()) -1; i > panel_index;
+         --i) {
+      gfx::Rect this_bounds = panels_[i]->GetBounds();
+      this_bounds.set_x(this_bounds.x() + delta);
+      panels_[i]->SetPanelBounds(this_bounds);
+    }
+  }
+
+  // The panel height:
+  // * cannot grow or shrink to go beyond [min_height, max_height]
+  int new_height = preferred_window_size.height();
+  if (new_height > panel->max_size().height())
+    new_height = panel->max_size().height();
+  if (new_height < panel->min_size().height())
+    new_height = panel->min_size().height();
+
+  if (new_height != restored_height) {
+    // If the panel is not expanded, we only need to save the new restored
+    // height.
+    if (panel->expansion_state() == Panel::EXPANDED) {
+      bounds.set_y(bounds.y() - new_height + bounds.height());
+      bounds.set_height(new_height);
+    } else {
+      panel->SetRestoredHeight(new_height);
+    }
+  }
+
+  panel->SetPanelBounds(bounds);
+
+  UpdateMaxSizeForAllPanels();
+}
+
 bool PanelManager::ShouldBringUpTitlebars(int mouse_x, int mouse_y) const {
   // We should always bring up the titlebar if the mouse is over the
   // visible auto-hiding bottom bar.
@@ -410,6 +489,7 @@ int PanelManager::GetBottomPositionForExpansionState(
     bottom += auto_hiding_desktop_bar_->GetThickness(
         AutoHidingDesktopBar::ALIGN_BOTTOM);
   }
+
   return bottom;
 }
 
@@ -450,6 +530,8 @@ void PanelManager::Rearrange(Panels::iterator iter_to_start,
 
     rightmost_position = new_bounds.x() - kPanelsHorizontalSpacing;
   }
+
+  UpdateMaxSizeForAllPanels();
 }
 
 void PanelManager::RemoveAll() {
@@ -468,3 +550,20 @@ void PanelManager::RemoveAll() {
 bool PanelManager::is_dragging_panel() const {
   return dragging_panel_index_ != kInvalidPanelIndex;
 }
+
+void PanelManager::UpdateMaxSizeForAllPanels() {
+  if (!auto_sizing_enabled_)
+    return;
+
+  for (Panels::const_iterator iter = panels_.begin();
+       iter != panels_.end(); ++iter) {
+    Panel* panel = *iter;
+    // A panel can at most grow to take over all the avaialble space that is
+    // returned by GetRightMostAvaialblePosition.
+    int width_can_grow_to =
+        panel->GetBounds().width() + GetRightMostAvaialblePosition();
+    panel->SetMaxSize(gfx::Size(
+        std::min(width_can_grow_to, GetMaxPanelWidth()),
+        GetMaxPanelHeight()));
+  }
+}
diff --git a/chrome/browser/ui/panels/panel_manager.h b/chrome/browser/ui/panels/panel_manager.h
index 998f91f..27d0f5f 100644
--- a/chrome/browser/ui/panels/panel_manager.h
+++ b/chrome/browser/ui/panels/panel_manager.h
@@ -45,6 +45,11 @@ class PanelManager : public AutoHidingDesktopBar::Observer,
   void Drag(int delta_x);
   void EndDragging(bool cancelled);
 
+  // Invoked when the preferred window size of the given panel might need to
+  // get changed.
+  void OnPreferredWindowSizeChanged(
+      Panel* panel, const gfx::Size& preferred_window_size);
+
   // Returns true if we should bring up the titlebars, given the current mouse
   // point.
   bool ShouldBringUpTitlebars(int mouse_x, int mouse_y) const;
@@ -74,6 +79,10 @@ class PanelManager : public AutoHidingDesktopBar::Observer,
     auto_hiding_desktop_bar_ = auto_hiding_desktop_bar;
   }
 
+  void enable_auto_sizing(bool enabled) {
+    auto_sizing_enabled_ = enabled;
+  }
+
   void SetWorkAreaForTesting(const gfx::Rect& work_area) {
     SetWorkArea(work_area);
   }
@@ -128,8 +137,14 @@ class PanelManager : public AutoHidingDesktopBar::Observer,
   // Does the real job of bringing up or down the titlebars.
   void DoBringUpOrDownTitlebars(bool bring_up);
 
+  int GetMaxPanelWidth() const;
+  int GetMaxPanelHeight() const;
   int GetRightMostAvaialblePosition() const;
 
+  // Updates the maximum size of each panel as the result of adding, removing,
+  // or sizing panels.
+  void UpdateMaxSizeForAllPanels();
+
   Panels panels_;
 
   // Stores the panels that are pending to remove. We want to delay the removal
@@ -164,6 +179,11 @@ class PanelManager : public AutoHidingDesktopBar::Observer,
 
   ScopedRunnableMethodFactory<PanelManager> method_factory_;
 
+  // Whether or not bounds will be updated when the preferred content size is
+  // changed. The testing code could set this flag to false so that other tests
+  // will not be affected.
+  bool auto_sizing_enabled_;
+
   static const int kPanelsHorizontalSpacing = 4;
 
   DISALLOW_COPY_AND_ASSIGN(PanelManager);
diff --git a/chrome/browser/ui/views/tab_contents/tab_contents_view_touch.cc b/chrome/browser/ui/views/tab_contents/tab_contents_view_touch.cc
index 492650b..1e13c51 100644
--- a/chrome/browser/ui/views/tab_contents/tab_contents_view_touch.cc
+++ b/chrome/browser/ui/views/tab_contents/tab_contents_view_touch.cc
@@ -222,9 +222,6 @@ void TabContentsViewTouch::RestoreFocus() {
   }
 }
 
-void TabContentsViewTouch::UpdatePreferredSize(const gfx::Size& pref_size) {
-}
-
 bool TabContentsViewTouch::IsDoingDrag() const {
   return false;
 }
diff --git a/chrome/browser/ui/views/tab_contents/tab_contents_view_touch.h b/chrome/browser/ui/views/tab_contents/tab_contents_view_touch.h
index 65ac649..6397668 100644
--- a/chrome/browser/ui/views/tab_contents/tab_contents_view_touch.h
+++ b/chrome/browser/ui/views/tab_contents/tab_contents_view_touch.h
@@ -65,7 +65,6 @@ class TabContentsViewTouch : public TabContentsView, public views::View {
   virtual void SetInitialFocus() OVERRIDE;
   virtual void StoreFocus() OVERRIDE;
   virtual void RestoreFocus() OVERRIDE;
-  virtual void UpdatePreferredSize(const gfx::Size& pref_size) OVERRIDE;
   virtual bool IsDoingDrag() const OVERRIDE;
   virtual void CancelDragAndCloseTab() OVERRIDE;
   virtual bool IsEventTracking() const OVERRIDE;
diff --git a/chrome/browser/ui/views/tab_contents/tab_contents_view_views.cc b/chrome/browser/ui/views/tab_contents/tab_contents_view_views.cc
index ab91362..0eab11bb 100644
--- a/chrome/browser/ui/views/tab_contents/tab_contents_view_views.cc
+++ b/chrome/browser/ui/views/tab_contents/tab_contents_view_views.cc
@@ -220,9 +220,6 @@ void TabContentsViewViews::RestoreFocus() {
   }
 }
 
-void TabContentsViewViews::UpdatePreferredSize(const gfx::Size& pref_size) {
-}
-
 bool TabContentsViewViews::IsDoingDrag() const {
   return native_tab_contents_view_->IsDoingDrag();
 }
diff --git a/chrome/browser/ui/views/tab_contents/tab_contents_view_views.h b/chrome/browser/ui/views/tab_contents/tab_contents_view_views.h
index 8c6b09e..b41f796 100644
--- a/chrome/browser/ui/views/tab_contents/tab_contents_view_views.h
+++ b/chrome/browser/ui/views/tab_contents/tab_contents_view_views.h
@@ -64,7 +64,6 @@ class TabContentsViewViews : public views::Widget,
   virtual void SetInitialFocus() OVERRIDE;
   virtual void StoreFocus() OVERRIDE;
   virtual void RestoreFocus() OVERRIDE;
-  virtual void UpdatePreferredSize(const gfx::Size& pref_size) OVERRIDE;
   virtual bool IsDoingDrag() const OVERRIDE;
   virtual void CancelDragAndCloseTab() OVERRIDE;
   virtual bool IsEventTracking() const;
diff --git a/chrome/test/data/update-preferred-size.html b/chrome/test/data/update-preferred-size.html
new file mode 100644
index 0000000..76e3f3f
--- /dev/null
+++ b/chrome/test/data/update-preferred-size.html
@@ -0,0 +1,18 @@
+<html>
+
+<head>
+<script>
+function changeSize(delta) {
+  var elem = document.getElementById("textInput");
+  elem.size = elem.size + delta;
+}
+</script>
+</head>
+
+<body>
+
+Hello<br/>
+<input id="textInput" type="text" size="5"><br/>
+
+</body>
+</html>
\ No newline at end of file