Enable the in-browser thumbnailing by default on supported platforms.

This CL flips --enable-in-browser-thumbnailing to --disable-inbrowser-thumbnailing, and enables the in-browser thumbnailing by default on the following platforms.
- Windows Vista or later
- Mac
- Chrome OS

On the following platform, in-browser thumbnailing is not enabled because it's not supported yet.
- Non-Aura (GTK) Linux
- Windows XP

BUG=120003
TEST=Manually tested on each platform

Review URL: https://chromiumcodereview.appspot.com/10310153

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@139748 0039d316-1c4b-4281-b951-d872f2087c98

9 files changed, 61 insertions, 17 deletions

diff --git a/chrome/browser/chrome_content_browser_client.cc b/chrome/browser/chrome_content_browser_client.cc
index 3552195..9735799 100644
--- a/chrome/browser/chrome_content_browser_client.cc
+++ b/chrome/browser/chrome_content_browser_client.cc
@@ -763,12 +763,12 @@ void ChromeContentBrowserClient::AppendExtraCommandLineSwitches(
       switches::kDisableAsynchronousSpellChecking,
       switches::kDisableBundledPpapiFlash,
       switches::kDisableExtensionsResourceWhitelist,
+      switches::kDisableInBrowserThumbnailing,
       switches::kDumpHistogramsOnExit,
       switches::kEnableBenchmarking,
       switches::kEnableBundledPpapiFlash,
       switches::kEnableCrxlessWebApps,
       switches::kEnableExperimentalExtensionApis,
-      switches::kEnableInBrowserThumbnailing,
       switches::kEnableIPCFuzzing,
       switches::kEnableNaCl,
       switches::kEnableNaClIPCProxy,
diff --git a/chrome/browser/ui/tab_contents/tab_contents_wrapper.cc b/chrome/browser/ui/tab_contents/tab_contents_wrapper.cc
index b9c464e..b1e87e6c 100644
--- a/chrome/browser/ui/tab_contents/tab_contents_wrapper.cc
+++ b/chrome/browser/ui/tab_contents/tab_contents_wrapper.cc
@@ -47,6 +47,7 @@
 #include "chrome/browser/view_type_utils.h"
 #include "chrome/common/chrome_notification_types.h"
 #include "chrome/common/chrome_switches.h"
+#include "chrome/common/thumbnail_support.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/web_contents.h"
 
@@ -148,8 +149,7 @@ TabContentsWrapper::TabContentsWrapper(WebContents* contents)
 #endif
 
   // Start the in-browser thumbnailing if the feature is enabled.
-  if (CommandLine::ForCurrentProcess()->HasSwitch(
-          switches::kEnableInBrowserThumbnailing)) {
+  if (ShouldEnableInBrowserThumbnailing()) {
     thumbnail_generator_.reset(new ThumbnailGenerator);
     thumbnail_generator_->StartThumbnailing(web_contents_.get());
   }
diff --git a/chrome/chrome_common.gypi b/chrome/chrome_common.gypi
index 31135ad..222e34e 100644
--- a/chrome/chrome_common.gypi
+++ b/chrome/chrome_common.gypi
@@ -269,6 +269,8 @@
         'common/switch_utils.h',
         'common/thumbnail_score.cc',
         'common/thumbnail_score.h',
+        'common/thumbnail_support.cc',
+        'common/thumbnail_support.h',
         'common/time_format.cc',
         'common/time_format.h',
         'common/url_constants.cc',
diff --git a/chrome/common/chrome_switches.cc b/chrome/common/chrome_switches.cc
index c47195f..da4531f 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -321,6 +321,11 @@ const char kDisableHistoryURLProvider[]     = "disable-history-url-provider";
 const char kDisableImprovedDownloadProtection[] =
     "disable-improved-download-protection";
 
+// Disables the in-browser thumbnailing, which is more efficient than the
+// in-renderer thumbnailing, as we can use more information to determine if we
+// need to update thumbnails.
+const char kDisableInBrowserThumbnailing[]  = "disable-in-browser-thumbnailing";
+
 // Disable the internal Flash Player.
 const char kDisableInternalFlash[]          = "disable-internal-flash";
 
@@ -518,11 +523,6 @@ const char kEnableFileCookies[]             = "enable-file-cookies";
 // Without this flag, pipelining will never be used.
 const char kEnableHttpPipelining[]          = "enable-http-pipelining";
 
-// Enables the in-browser thumbnailing, which is more efficient than the
-// in-renderer thumbnailing, as we can use more information to determine if we
-// need to update thumbnails.
-const char kEnableInBrowserThumbnailing[]   = "enable-in-browser-thumbnailing";
-
 // Enables IPv6 support, even if probes suggest that it may not be fully
 // supported. Some probes may require internet connections, and this flag will
 // allow support independent of application testing. This flag overrides
diff --git a/chrome/common/chrome_switches.h b/chrome/common/chrome_switches.h
index c2ccf9b..78e227b 100644
--- a/chrome/common/chrome_switches.h
+++ b/chrome/common/chrome_switches.h
@@ -96,6 +96,7 @@ extern const char kDisableFlashSandbox[];
 extern const char kDisableHistoryQuickProvider[];
 extern const char kDisableHistoryURLProvider[];
 extern const char kDisableImprovedDownloadProtection[];
+extern const char kDisableInBrowserThumbnailing[];
 extern const char kDisableInternalFlash[];
 extern const char kDisableIPv6[];
 extern const char kDisableIPPooling[];
@@ -150,7 +151,6 @@ extern const char kEnableExtensionActivityUI[];
 extern const char kEnableExtensionTimelineApi[];
 extern const char kEnableFileCookies[];
 extern const char kEnableHttpPipelining[];
-extern const char kEnableInBrowserThumbnailing[];
 extern const char kEnableIPv6[];
 extern const char kEnableIPCFuzzing[];
 extern const char kEnableIPPooling[];
diff --git a/chrome/common/thumbnail_support.cc b/chrome/common/thumbnail_support.cc
new file mode 100644
index 0000000..ef378f2
--- /dev/null
+++ b/chrome/common/thumbnail_support.cc
@@ -0,0 +1,30 @@
+// 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/common/thumbnail_support.h"
+
+#include "base/command_line.h"
+#include "chrome/common/chrome_switches.h"
+
+#if defined(OS_WIN)
+#include "base/win/windows_version.h"
+#endif
+
+bool ShouldEnableInBrowserThumbnailing() {
+  if (CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kDisableInBrowserThumbnailing))
+    return false;
+
+#if defined(OS_WIN)
+  // Disables in-browser thumbnailing on Windows XP where not supported yet.
+  if (base::win::GetVersion() < base::win::VERSION_VISTA)
+    return false;
+  return true;
+#elif defined(OS_LINUX) && !defined(USE_AURA)
+  // Disables in-browser thumbnailing on non-Aura Linux where not supported yet.
+  return false;
+#else
+  return true;
+#endif
+}
diff --git a/chrome/common/thumbnail_support.h b/chrome/common/thumbnail_support.h
new file mode 100644
index 0000000..cb642ae
--- /dev/null
+++ b/chrome/common/thumbnail_support.h
@@ -0,0 +1,16 @@
+// 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.
+
+#ifndef CHROME_COMMON_THUMBNAIL_SUPPORT_H_
+#define CHROME_COMMON_THUMBNAIL_SUPPORT_H_
+#pragma once
+
+// TODO(mazda): Remove this file once in-browser thumbnailing is supported on
+// all platforms.
+
+// Returns true if in-browser thumbnailing is supported and not disabled by the
+// command line flag.
+bool ShouldEnableInBrowserThumbnailing();
+
+#endif  // CHROME_COMMON_THUMBNAIL_SUPPORT_H_
diff --git a/chrome/renderer/chrome_render_view_observer.cc b/chrome/renderer/chrome_render_view_observer.cc
index 2371ac2..742b1e9 100644
--- a/chrome/renderer/chrome_render_view_observer.cc
+++ b/chrome/renderer/chrome_render_view_observer.cc
@@ -17,6 +17,7 @@
 #include "chrome/common/prerender_messages.h"
 #include "chrome/common/render_messages.h"
 #include "chrome/common/thumbnail_score.h"
+#include "chrome/common/thumbnail_support.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/renderer/chrome_render_process_observer.h"
 #include "chrome/renderer/content_settings_observer.h"
@@ -832,12 +833,10 @@ void ChromeRenderViewObserver::CapturePageInfo(bool preliminary_capture) {
   }
 
   // Generate the thumbnail here if the in-browser thumbnailing isn't
-  // enabled. TODO(satorux): Remove this and related code once
-  // crbug.com/65936 is complete.
-  if (!CommandLine::ForCurrentProcess()->HasSwitch(
-          switches::kEnableInBrowserThumbnailing)) {
+  // enabled. TODO(mazda): Remove this and related code once in-browser
+  // thumbnailing is supported on all platforms (http://crbug.com/120003).
+  if (!ShouldEnableInBrowserThumbnailing())
     CaptureThumbnail();
-  }
 
 #if defined(ENABLE_SAFE_BROWSING)
   // Will swap out the string.
diff --git a/chrome/test/perf/rendering/latency_tests.cc b/chrome/test/perf/rendering/latency_tests.cc
index 6e94151..de72c18 100644
--- a/chrome/test/perf/rendering/latency_tests.cc
+++ b/chrome/test/perf/rendering/latency_tests.cc
@@ -229,9 +229,6 @@ void LatencyTest::SetUpCommandLine(CommandLine* command_line) {
       HasSwitch(switches::kEnableThreadedCompositing)) {
     command_line->AppendSwitch(switches::kEnableThreadedCompositing);
   }
-  // Default behavior is to thumbnail the tab after 0.5 seconds, causing
-  // a nasty frame hitch and disturbing the latency test. Fix that:
-  command_line->AppendSwitch(switches::kEnableInBrowserThumbnailing);
   command_line->AppendSwitch(switches::kDisableBackgroundNetworking);
 }