Revert of Remove EnableThreadedCompositing from the browser.

content/shell/common/shell_switches.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 "content/shell/common/shell_switches.h"
 
 namespace switches {
 
 // Allow access to external pages during layout tests.
 const char kAllowExternalPages[] = "allow-external-pages";
@@ skipping 16 matching lines @@
 // Enable accelerated 2D canvas.
 const char kEnableAccelerated2DCanvas[] = "enable-accelerated-2d-canvas";
 
 // Enable font antialiasing for pixel tests.
 const char kEnableFontAntialiasing[] = "enable-font-antialiasing";
 
 // Enables the leak detection of loading webpages. This allows us to check
 // whether or not reloading a webpage releases web-related objects correctly.
 const char kEnableLeakDetection[] = "enable-leak-detection";
 
-// Enabled threaded compositing for layout tests.
-const char kEnableThreadedCompositing[] = "enable-threaded-compositing";
-
 // Encode binary layout test results (images, audio) using base64.
 const char kEncodeBinary[] = "encode-binary";
 
 // Exposes the window.internals object to JavaScript for interactive development
 // and debugging of layout tests that rely on it.
 const char kExposeInternalsForTesting[] = "expose-internals-for-testing";
 
 // Registers additional font files on Windows (for fonts outside the usual
 // %WINDIR%\Fonts location). Multiple files can be used by separating them
 // with a semicolon (;).
 const char kRegisterFontFiles[] = "register-font-files";
 
 // This makes us disable some web-platform runtime features so that we test
 // content_shell as if it was a stable release. It is only followed when
 // kDumpRenderTree is set. For the features' level, see
 // http://dev.chromium.org/blink/runtime-enabled-features.
 const char kStableReleaseMode[] = "stable-release-mode";
 
 }  // namespace switches