Revert 231699 "Remove kNaturalScrollDefault."

Many tests started failing at ui::ShouldDefaultToNaturalScroll(), e.g.,
http://build.chromium.org/p/chromium.chromiumos/builders/Linux%20ChromiumOS%20Tests%20%28dbg%29%281%29/builds/26125/steps/unit_tests/logs/TestFocusNotification

> Remove kNaturalScrollDefault.
> 
> We have a runtime check - IsTouchDevicePresent, so just use that instead of the flag.
> 
> BUG=NONE
> TEST=manual
> 
> Review URL: https://codereview.chromium.org/33913003

TBR=achuith@chromium.org

Review URL: https://codereview.chromium.org/52223002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@231779 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/chromeos/chrome_browser_main_chromeos.cc

@@ -644,8 +644,11 @@ void ChromeBrowserMainPartsChromeos::PreBrowserStart() {
   // adjusting the oom priority.
   g_browser_process->platform_part()->oom_priority_manager()->Start();
 
-  if (ui::ShouldDefaultToNaturalScroll())
+  if (ui::ShouldDefaultToNaturalScroll()) {
+    CommandLine::ForCurrentProcess()->AppendSwitch(
+        chromeos::switches::kNaturalScrollDefault);
     ui::SetNaturalScroll(true);
+  }
 
   ChromeBrowserMainPartsLinux::PreBrowserStart();
 }

chrome/browser/chromeos/login/chrome_restart_request.cc

@@ -193,6 +193,7 @@ std::string DeriveCommandLine(const GURL& start_url,
       chromeos::switches::kHasChromeOSDiamondKey,
       chromeos::switches::kHasChromeOSKeyboard,
       chromeos::switches::kLoginProfile,
+      chromeos::switches::kNaturalScrollDefault,
       ::switches::kEnableBrowserTextSubpixelPositioning,
       ::switches::kEnableWebkitTextSubpixelPositioning,
       views::corewm::switches::kNoDropShadows,

chrome/browser/chromeos/login/login_display_host_impl.cc

@@ -66,6 +66,7 @@
 #include "ui/compositor/layer.h"
 #include "ui/compositor/layer_animation_observer.h"
 #include "ui/compositor/scoped_layer_animation_settings.h"
+#include "ui/events/event_utils.h"
 #include "ui/gfx/rect.h"
 #include "ui/gfx/transform.h"
 #include "ui/views/focus/focus_manager.h"
@@ -920,6 +921,9 @@ void ShowLoginWizard(const std::string& first_screen_name) {
       prefs->GetBoolean(prefs::kOwnerTapToClickEnabled));
   }
 
+  ui::SetNaturalScroll(CommandLine::ForCurrentProcess()->HasSwitch(
+      switches::kNaturalScrollDefault));
+
   gfx::Rect screen_bounds(chromeos::CalculateScreenBounds(gfx::Size()));
 
   // Check whether we need to execute OOBE process.

chrome/browser/chromeos/preferences.cc

@@ -116,7 +116,8 @@ void Preferences::RegisterProfilePrefs(
       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
   registry->RegisterBooleanPref(
       prefs::kNaturalScroll,
-      ui::ShouldDefaultToNaturalScroll(),
+      CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kNaturalScrollDefault),
       user_prefs::PrefRegistrySyncable::SYNCABLE_PRIORITY_PREF);
   registry->RegisterBooleanPref(
       prefs::kPrimaryMouseButtonRight,
@@ -585,7 +586,8 @@ void Preferences::OnIsSyncingChanged() {
 
 void Preferences::ForceNaturalScrollDefault() {
   DVLOG(1) << "ForceNaturalScrollDefault";
-  if (ui::ShouldDefaultToNaturalScroll() &&
+  if (CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kNaturalScrollDefault) &&
       prefs_->IsSyncing() &&
       !prefs_->GetUserPrefValue(prefs::kNaturalScroll)) {
     DVLOG(1) << "Natural scroll forced to true";

chrome/browser/ui/views/ash/tab_scrubber_browsertest.cc

@@ -41,6 +41,9 @@ class TabScrubberTest : public InProcessBrowserTest,
   }
 
   virtual void SetUpCommandLine(CommandLine* command_line) OVERRIDE {
+#if defined(OS_CHROMEOS)
+    command_line->AppendSwitch(chromeos::switches::kNaturalScrollDefault);
+#endif
     command_line->AppendSwitch(switches::kOpenAsh);
   }
 
@@ -51,8 +54,6 @@ class TabScrubberTest : public InProcessBrowserTest,
     ash::Shell* shell = ash::Shell::GetInstance();
     shell->event_transformation_handler()->set_transformation_mode(
         ash::internal::EventTransformationHandler::TRANSFORM_NONE);
-
-    ui::SetNaturalScroll(true);
   }
 
   virtual void CleanUpOnMainThread() OVERRIDE {

chromeos/chromeos_switches.cc

@@ -157,6 +157,9 @@ const char kLoginProfile[]                  = "login-profile";
 // Specifies the user which is already logged in.
 const char kLoginUser[]                     = "login-user";
 
+// Enables natural scroll by default.
+const char kNaturalScrollDefault[]          = "enable-natural-scroll-default";
+
 // Skips all other OOBE pages after user login.
 const char kOobeSkipPostLogin[]             = "oobe-skip-postlogin";
 

chromeos/chromeos_switches.h

@@ -62,6 +62,7 @@ CHROMEOS_EXPORT extern const char kLoginManager[];
 CHROMEOS_EXPORT extern const char kLoginPassword[];
 CHROMEOS_EXPORT extern const char kLoginProfile[];
 CHROMEOS_EXPORT extern const char kLoginUser[];
+CHROMEOS_EXPORT extern const char kNaturalScrollDefault[];
 CHROMEOS_EXPORT extern const char kOobeSkipPostLogin[];
 CHROMEOS_EXPORT extern const char kSkipHWIDCheck[];
 CHROMEOS_EXPORT extern const char kSmsTestMessages[];