Mac: Prevent NTP mousewheel events from being suppressed on Lion.

chrome/browser/ui/webui/ntp/ntp_resource_cache.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/webui/ntp/ntp_resource_cache.h"
 
 #include <vector>
 
 #include "base/command_line.h"
 #include "base/file_util.h"
@@ skipping 40 matching lines @@
 #include "ui/gfx/sys_color_change_listener.h"
 
 #if defined(OS_WIN) || defined(TOOLKIT_VIEWS)
 #include "chrome/browser/ui/views/bookmarks/bookmark_bar_view.h"
 #elif defined(OS_MACOSX)
 #include "chrome/browser/ui/cocoa/bookmarks/bookmark_bar_constants.h"
 #elif defined(TOOLKIT_GTK)
 #include "chrome/browser/ui/gtk/bookmarks/bookmark_bar_gtk.h"
 #endif
 
+#if defined(OS_MACOSX)
+#include "base/mac/mac_util.h"
+#endif
+
 using base::Time;
 using content::BrowserThread;
 
 namespace {
 
 // The URL for the the Learn More page shown on incognito new tab.
 const char kLearnMoreIncognitoUrl[] =
 #if defined(OS_CHROMEOS)
     "https://www.google.com/support/chromeos/bin/answer.py?answer=95464";
 #else
@@ skipping 98 matching lines @@
 
 // Is the current time within a given date range?
 bool InDateRange(double begin, double end) {
   Time start_time = Time::FromDoubleT(begin);
   Time end_time = Time::FromDoubleT(end);
   return start_time < Time::Now() && end_time > Time::Now();
 }
 
 }  // namespace
 
-NTPResourceCache::NTPResourceCache(Profile* profile) : profile_(profile) {
+NTPResourceCache::NTPResourceCache(Profile* profile)
+    : profile_(profile), isSwipeTrackingFromScrollEventsEnabled_(false) {
   registrar_.Add(this, chrome::NOTIFICATION_BROWSER_THEME_CHANGED,
                  content::Source<ThemeService>(
                      ThemeServiceFactory::GetForProfile(profile)));
   registrar_.Add(this, chrome::NOTIFICATION_PROMO_RESOURCE_STATE_CHANGED,
                  content::NotificationService::AllSources());
   registrar_.Add(this, chrome::NTP4_INTRO_PREF_CHANGED,
                  content::NotificationService::AllSources());
 
   // Watch for pref changes that cause us to need to invalidate the HTML cache.
   pref_change_registrar_.Init(profile_->GetPrefs());
   pref_change_registrar_.Add(prefs::kSyncAcknowledgedSyncTypes, this);
   pref_change_registrar_.Add(prefs::kShowBookmarkBar, this);
   pref_change_registrar_.Add(prefs::kNtpShownPage, this);
   pref_change_registrar_.Add(prefs::kSyncPromoShowNTPBubble, this);
 }
 
 NTPResourceCache::~NTPResourceCache() {}
 
+bool NTPResourceCache::InvalidateNewTabCache() {

[Evan Stade, 2012/04/17 21:29:53]

s/InvalidateNewTabCache/NewTabCacheNeedsRefresh/g

(InvalidateNewTabCache sounds like a verb rather than a question)

[Patrick Dubroy, 2012/04/18 14:43:06]

Done.

+#if defined(OS_MACOSX)
+  // Invalidate if the current value is different from the cached value.
+  bool swipe_tracking_enabled =
+      base::mac::IsSwipeTrackingFromScrollEventsEnabled();
+  if (swipe_tracking_enabled != isSwipeTrackingFromScrollEventsEnabled_) {
+    isSwipeTrackingFromScrollEventsEnabled_ = swipe_tracking_enabled;
+    return true;
+  }
+#endif
+  return false;
+}
+
 RefCountedMemory* NTPResourceCache::GetNewTabHTML(bool is_incognito) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   if (is_incognito) {
     if (!new_tab_incognito_html_.get())
       CreateNewTabIncognitoHTML();
   } else {
-    if (!new_tab_html_.get())
+    if (!new_tab_html_.get() || InvalidateNewTabCache())
       CreateNewTabHTML();
   }
   return is_incognito ? new_tab_incognito_html_.get() :
                         new_tab_html_.get();
 }
 
 RefCountedMemory* NTPResourceCache::GetNewTabCSS(bool is_incognito) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   if (is_incognito) {
     if (!new_tab_incognito_css_.get())
@@ skipping 143 matching lines @@
   localized_strings.SetBoolean("appInstallHintEnabled",
       NewTabUI::ShouldShowAppInstallHint());
   localized_strings.SetString("appInstallHintText",
       l10n_util::GetStringUTF16(IDS_NEW_TAB_APP_INSTALL_HINT_LABEL));
   localized_strings.SetBoolean("isSuggestionsPageEnabled",
       NewTabUI::IsSuggestionsPageEnabled());
   localized_strings.SetBoolean("showApps", NewTabUI::ShouldShowApps());
   localized_strings.SetString("hideSessionMenuItemText",
       l10n_util::GetStringUTF16(IDS_POLICY_HIDE));
 
+  // On Mac OS X 10.7+, horizontal scrolling can be treated as a back or
+  // forward gesture. Pass through a flag that indicates whether or not that
+  // feature is enabled.
+#if defined(OS_MACOSX)
+  localized_strings.SetBoolean("isSwipeTrackingFromScrollEventsEnabled",
+      base::mac::IsSwipeTrackingFromScrollEventsEnabled());

[Evan Stade, 2012/04/17 21:29:53]

use the member var to avoid these ifdefs

[Patrick Dubroy, 2012/04/18 14:43:06]

Done.

+#else
+  localized_strings.SetBoolean("isSwipeTrackingFromScrollEventsEnabled",
+      false);
+#endif
+
 #if defined(OS_CHROMEOS)
   localized_strings.SetString("expandMenu",
       l10n_util::GetStringUTF16(IDS_NEW_TAB_CLOSE_MENU_EXPAND));
 #endif
 
   NewTabPageHandler::GetLocalizedValues(profile_, &localized_strings);
   NTPLoginHandler::GetLocalizedValues(profile_, &localized_strings);
 
   // Don't initiate the sync related message passing with the page if the sync
   // code is not present.
@@ skipping 174 matching lines @@
   // Get our template.
   static const base::StringPiece new_tab_theme_css(
       ResourceBundle::GetSharedInstance().GetRawDataResource(
           IDR_NEW_TAB_4_THEME_CSS));
 
   // Create the string from our template and the replacements.
   std::string css_string;
   css_string = ReplaceStringPlaceholders(new_tab_theme_css, subst, NULL);
   new_tab_css_ = base::RefCountedString::TakeString(&css_string);
 }