Fix for out-of-sync scale factor issue

chrome/browser/ui/startup/startup_browser_creator_impl.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/startup/startup_browser_creator_impl.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "base/bind.h"
@@ skipping 79 matching lines @@
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_view.h"
 #include "grit/locale_settings.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/rect.h"
 #include "ui/gfx/screen.h"
 
 #if defined(USE_ASH)
 #include "ash/launcher/launcher_types.h"
+#include "ash/shell.h"
+#include "ui/aura/window.h"
 #endif
 
 #if defined(OS_MACOSX)
 #include "base/mac/mac_util.h"
 #include "chrome/browser/ui/cocoa/keystone_infobar_delegate.h"
 #endif
 
 #if defined(TOOLKIT_GTK)
 #include "chrome/browser/ui/gtk/gtk_util.h"
 #endif
@@ skipping 689 matching lines @@
     browser = new Browser(Browser::CreateParams(profile_));
   } else {
 #if defined(TOOLKIT_GTK)
     // Setting the time of the last action on the window here allows us to steal
     // focus, which is what the user wants when opening a new tab in an existing
     // browser window.
     gtk_util::SetWMLastUserActionTime(browser->window()->GetNativeWindow());
 #endif
   }
 
+#if defined(USE_ASH)
+  if (ash::Shell::HasInstance()) {
+    // Set the browser's root window to be an active root window now so
+    // that that web contents can determine correct scale factor for the
+    // renderer. This is a short term fix for crbug.com/155201.  Without
+    // this, the renderer may use wrong scale factor first, then
+    // switched to the correct scale factor, which can cause race
+    // condition and lead to the results rendered at wrong scale factor.
+    // Long term fix is tracked in crbug.com/15543.
+    ash::Shell::GetInstance()->set_active_root_window(
+        browser->window()->GetNativeWindow()->GetRootWindow());
+  }
+#endif
+
   // In kiosk mode, we want to always be fullscreen, so switch to that now.
   if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kKioskMode))
     chrome::ToggleFullscreenMode(browser);
 
   bool first_tab = true;
   for (size_t i = 0; i < tabs.size(); ++i) {
     // We skip URLs that we'd have to launch an external protocol handler for.
     // This avoids us getting into an infinite loop asking ourselves to open
     // a URL, should the handler be (incorrectly) configured to be us. Anyone
     // asking us to open such a URL should really ask the handler directly.
@@ skipping 206 matching lines @@
 
 #if !defined(OS_WIN) || defined(USE_AURA)
 // static
 bool StartupBrowserCreatorImpl::OpenStartupURLsInExistingBrowser(
     Profile* profile,
     const std::vector<GURL>& startup_urls) {
   return false;
 }
 #endif