Disable touchpad settings for non-touchpad devices in 912

BUG=chromium-os:21361
TEST=System options on non-touchpad device should not show touchpad settings.
Review URL: http://codereview.chromium.org/8564023

git-svn-id: svn://svn.chromium.org/chrome/branches/912/src@110474 0039d316-1c4b-4281-b951-d872f2087c98

6 files changed, 65 insertions, 13 deletions

diff --git a/chrome/browser/chromeos/system/touchpad_settings.cc b/chrome/browser/chromeos/system/touchpad_settings.cc
index 0257cc1..449bdc5 100644
--- a/chrome/browser/chromeos/system/touchpad_settings.cc
+++ b/chrome/browser/chromeos/system/touchpad_settings.cc
@@ -19,24 +19,40 @@ namespace system {
 namespace touchpad_settings {
 namespace {
 const char* kTpControl = "/opt/google/touchpad/tpcontrol";
-}  // namespace
+
+bool TPCtrlExists() {
+  return file_util::PathExists(FilePath(kTpControl));
+}
 
 // Launches the tpcontrol command asynchronously, if it exists.
 void LaunchTpControl(const std::vector<std::string>& argv) {
-  if (!system::runtime_environment::IsRunningOnChromeOS()) {
-    // Do nothing on Linux desktop, as the command does not exist.
+  if (!TPCtrlExists())
     return;
-  }
 
-  if (!file_util::PathExists(FilePath(argv[0]))) {
-    LOG(ERROR) << argv[0] << " not found";
-    return;
-  }
+  base::LaunchProcess(CommandLine(argv), base::LaunchOptions(), NULL);
+}
 
-  base::LaunchOptions options;
-  options.wait = false;  // Launch asynchronously.
+}  // namespace
+
+bool TouchpadExists() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
+  static bool init = false;
+  static bool exists = false;
+
+  if (init)
+    return exists;
 
-  base::LaunchProcess(CommandLine(argv), options, NULL);
+  init = true;
+  if (!TPCtrlExists())
+    return exists;
+
+  std::vector<std::string> argv;
+  argv.push_back(kTpControl);
+  argv.push_back("status");
+  std::string output;
+  // On devices with no touchpad, output is empty.
+  exists = base::GetAppOutput(CommandLine(argv), &output) && !output.empty();
+  return exists;
 }
 
 void SetSensitivity(int value) {
diff --git a/chrome/browser/chromeos/system/touchpad_settings.h b/chrome/browser/chromeos/system/touchpad_settings.h
index acb940d..ed8b310 100644
--- a/chrome/browser/chromeos/system/touchpad_settings.h
+++ b/chrome/browser/chromeos/system/touchpad_settings.h
@@ -10,6 +10,8 @@ namespace chromeos {
 namespace system {
 namespace touchpad_settings {
 
+bool TouchpadExists();
+
 // Sets the touchpad sensitivity in range from 1 to 5.
 void SetSensitivity(int value);
 
diff --git a/chrome/browser/resources/options/chromeos/system_options.html b/chrome/browser/resources/options/chromeos/system_options.html
index b870812..a6c2563 100644
--- a/chrome/browser/resources/options/chromeos/system_options.html
+++ b/chrome/browser/resources/options/chromeos/system_options.html
@@ -33,7 +33,7 @@
         </div>
       </section>
     </if>
-    <section>
+    <section id="touchpad-controls" hidden>
       <h3 i18n-content="touchpad"></h3>
       <div class="option-control-table">
         <span class="option-name" i18n-content="sensitivity"></span>
diff --git a/chrome/browser/resources/options/chromeos/system_options.js b/chrome/browser/resources/options/chromeos/system_options.js
index 75c8777..0b4e9dd 100644
--- a/chrome/browser/resources/options/chromeos/system_options.js
+++ b/chrome/browser/resources/options/chromeos/system_options.js
@@ -163,6 +163,13 @@ cr.define('options', function() {
     }, 2000);
   }
 
+  /**
+   * Displays the Touchpad Controls section when we detect a touchpad.
+   */
+  SystemOptions.showTouchpadControls = function() {
+    $('touchpad-controls').hidden = false;
+  };
+
   // Export
   return {
     SystemOptions: SystemOptions
diff --git a/chrome/browser/ui/webui/options/chromeos/system_options_handler.cc b/chrome/browser/ui/webui/options/chromeos/system_options_handler.cc
index d465645..89f3e0f 100644
--- a/chrome/browser/ui/webui/options/chromeos/system_options_handler.cc
+++ b/chrome/browser/ui/webui/options/chromeos/system_options_handler.cc
@@ -20,6 +20,7 @@
 #include "chrome/browser/chromeos/dbus/dbus_thread_manager.h"
 #include "chrome/browser/chromeos/dbus/power_manager_client.h"
 #include "chrome/browser/chromeos/language_preferences.h"
+#include "chrome/browser/chromeos/system/touchpad_settings.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/prefs/pref_service.h"
 #include "chrome/browser/profiles/profile.h"
@@ -35,6 +36,14 @@
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/resource/resource_bundle.h"
 
+namespace {
+
+void TouchpadExistsFileThread(bool* exists) {
+  *exists = chromeos::system::touchpad_settings::TouchpadExists();
+}
+
+}
+
 SystemOptionsHandler::SystemOptionsHandler()
     : chromeos::CrosOptionsPageUIHandler(
         new chromeos::SystemSettingsProvider()) {
@@ -128,6 +137,18 @@ void SystemOptionsHandler::Initialize() {
     web_ui_->CallJavascriptFunction(
         "options.SystemOptions.showBluetoothSettings");
   }
+
+  bool* exists = new bool;
+  BrowserThread::PostTaskAndReply(BrowserThread::FILE, FROM_HERE,
+      base::Bind(&TouchpadExistsFileThread, exists),
+      base::Bind(&SystemOptionsHandler::TouchpadExists, AsWeakPtr(), exists));
+}
+
+void SystemOptionsHandler::TouchpadExists(bool* exists) {
+  if (*exists)
+    web_ui_->CallJavascriptFunction(
+        "options.SystemOptions.showTouchpadControls");
+  delete exists;
 }
 
 void SystemOptionsHandler::RegisterMessages() {
diff --git a/chrome/browser/ui/webui/options/chromeos/system_options_handler.h b/chrome/browser/ui/webui/options/chromeos/system_options_handler.h
index 082e6df..ff2a76c 100644
--- a/chrome/browser/ui/webui/options/chromeos/system_options_handler.h
+++ b/chrome/browser/ui/webui/options/chromeos/system_options_handler.h
@@ -6,6 +6,7 @@
 #define CHROME_BROWSER_UI_WEBUI_OPTIONS_CHROMEOS_SYSTEM_OPTIONS_HANDLER_H_
 #pragma once
 
+#include "base/memory/weak_ptr.h"
 #include "chrome/browser/ui/webui/options/chromeos/cros_options_page_ui_handler.h"
 
 namespace base {
@@ -13,7 +14,9 @@ class DictionaryValue;
 }
 
 // ChromeOS system options page UI handler.
-class SystemOptionsHandler : public chromeos::CrosOptionsPageUIHandler {
+class SystemOptionsHandler
+  : public chromeos::CrosOptionsPageUIHandler,
+    public base::SupportsWeakPtr<SystemOptionsHandler> {
  public:
   SystemOptionsHandler();
   virtual ~SystemOptionsHandler();
@@ -56,6 +59,9 @@ class SystemOptionsHandler : public chromeos::CrosOptionsPageUIHandler {
   // Called when emulating ChromeOS from a desktop environment.
   void GenerateFakeDeviceList();
 
+  // Callback for TouchpadHelper.
+  void TouchpadExists(bool* exists);
+
   DISALLOW_COPY_AND_ASSIGN(SystemOptionsHandler);
 };