Enable GPU process rendering of extensions on TOUCH_UI.

With this patch, the WebKit compositor produces the keyboard, login screen, and other WebUI elements (e.g. chrome://flags). This makes the keyboard animation smooth on the views-desktop.

BUG=none
TEST=use keyboard with --show-fps-counter on TOUCH_UI build; a red meter in the top left corner should appear

Review URL: http://codereview.chromium.org/7865016

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@100682 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/content/browser/tab_contents/tab_contents.cc b/content/browser/tab_contents/tab_contents.cc
index 061846bf..ac7404c 100644
--- a/content/browser/tab_contents/tab_contents.cc
+++ b/content/browser/tab_contents/tab_contents.cc
@@ -1814,7 +1814,10 @@
   // Force accelerated compositing and 2d canvas off for chrome:, about: and
   // chrome-devtools: pages (unless it's specifically allowed).
   if ((GetURL().SchemeIs(chrome::kChromeDevToolsScheme) ||
+#if !defined(TOUCH_UI)
+      // Allow accelerated compositing for keyboard and log in screen.
       GetURL().SchemeIs(chrome::kChromeUIScheme) ||
+#endif
       GetURL().SchemeIs(chrome::kAboutScheme)) &&
       !web_prefs.allow_webui_compositing) {
     web_prefs.accelerated_compositing_enabled = false;