CSS Media Query now reports touch-support accurately for Windows.

content/browser/web_contents/web_contents_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 "content/browser/web_contents/web_contents_impl.h"
 
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/stats_counters.h"
 #include "base/string16.h"
 #include "base/string_number_conversions.h"
 #include "base/string_util.h"
 #include "base/sys_info.h"
 #include "base/time.h"
 #include "base/utf_string_conversions.h"
+#include "base/win/windows_version.h"
 #include "content/browser/browser_plugin/old/old_browser_plugin_host.h"
 #include "content/browser/child_process_security_policy_impl.h"
 #include "content/browser/debugger/devtools_manager_impl.h"
 #include "content/browser/dom_storage/dom_storage_context_impl.h"
 #include "content/browser/dom_storage/session_storage_namespace_impl.h"
 #include "content/browser/download/download_stats.h"
 #include "content/browser/download/mhtml_generation_manager.h"
 #include "content/browser/download/save_package.h"
 #include "content/browser/gpu/gpu_data_manager_impl.h"
 #include "content/browser/gpu/gpu_process_host.h"
@@ skipping 491 matching lines @@
       !command_line.HasSwitch(switches::kDisableAcceleratedVideo);
   prefs.fullscreen_enabled =
       !command_line.HasSwitch(switches::kDisableFullScreen);
   prefs.css_regions_enabled =
       command_line.HasSwitch(switches::kEnableCssRegions);
   prefs.css_shaders_enabled =
       command_line.HasSwitch(switches::kEnableCssShaders);
   prefs.css_variables_enabled =
       command_line.HasSwitch(switches::kEnableCssVariables);
   prefs.device_supports_touch =
       ui::GetDisplayLayout() == ui::LAYOUT_TOUCH;

[Rick Byers, 2012/08/21 11:26:16]

You might as well remove this line now (or explicitly initialize to false) -
Windows was the only other case we cared about.

[girard, 2012/08/23 15:57:23]

Done.

 #if defined(USE_AURA) && defined(USE_X11)
   prefs.device_supports_touch |=
       ui::TouchFactory::GetInstance()->IsTouchDevicePresent();
 #endif
+#if defined(OS_WIN)
+  if (base::win::GetVersion() >= base::win::VERSION_WIN7)
+    // Docs: http://msdn.microsoft.com/en-us/library/dd371581(VS.85).aspx

[girard, 2012/08/20 21:15:18]

Q: Is it reasonable to leave a documentation link in the code?  This page
contains a lot of info on the return value(s), such as how to detect a
multi-touch, or pen vs touch, etc.

[sky, 2012/08/20 22:53:49]

Yes.

+    prefs.device_supports_touch = (::GetSystemMetrics(SM_DIGITIZER) > 0);

[girard, 2012/08/20 21:15:18]

Q: Would it be better to move this out to base::win::IsTouchSupported()?

[sky, 2012/08/20 22:53:49]

That sounds better to me.

[girard, 2012/08/23 15:57:23]

Done.

+#endif
 #if defined(OS_ANDROID)
   prefs.device_supports_mouse = false;
 #endif
 
 #if defined(OS_MACOSX)
   bool default_enable_scroll_animator = true;
 #else
   // On CrOS, the launcher always passes in the --enable flag.
   bool default_enable_scroll_animator = false;
 #endif
@@ skipping 2660 matching lines @@
       old_browser_plugin_host()->embedder_render_process_host();
   *embedder_container_id = old_browser_plugin_host()->instance_id();
   int embedder_process_id =
       embedder_render_process_host ? embedder_render_process_host->GetID() : -1;
   if (embedder_process_id != -1) {
     *embedder_channel_name =
         StringPrintf("%d.r%d", render_view_host->GetProcess()->GetID(),
                      embedder_process_id);
   }
 }