Revert 87592 - Re-enable in-browser thumbnailing for Linux and Chrome OS.

The in-browser thumbnailing does not work if
--force-compositing-mode is supplied. I don't know what would be the right way
to fix this. For now, we should just disable the in-browser thumbnailing,
until we have the right fix.

BUG=chromium-os:19731

The last valgrind error was fixed by r87590.

BUG=65936
TEST=confirm that thumbnails in the new tab page are updated properly

Review URL: http://codereview.chromium.org/6969091

TBR=satorux@chromium.org

Review URL: http://codereview.chromium.org/7762006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@98512 0039d316-1c4b-4281-b951-d872f2087c98

chrome/common/chrome_switches.cc

@@ -1238,13 +1238,8 @@ bool IsPrintPreviewEnabled() {
 }
 
 bool IsInBrowserThumbnailingEnabled() {
-#if defined(OS_LINUX) || defined(OS_CHROMEOS)
-  // The in-browser-thumbnailing is enabled for Linux and Chrome OS.
-  return true;
-#else
   return CommandLine::ForCurrentProcess()->HasSwitch(
       kEnableInBrowserThumbnailing);
-#endif
 }
 
 // -----------------------------------------------------------------------------