add --enable-spatial-navigation flag for testing

content/public/common/content_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/public/common/content_switches.h"
 
 namespace switches {
 
 // By default, file:// URIs cannot read other file:// URIs. This is an
 // override for developers who need the old behavior for testing.
@@ skipping 347 matching lines @@
 // Enables TLS cached info extension.
 const char kEnableSSLCachedInfo[]  = "enable-ssl-cached-info";
 
 // Cause the OS X sandbox write to syslog every time an access to a resource
 // is denied by the sandbox.
 const char kEnableSandboxLogging[]          = "enable-sandbox-logging";
 
 // Enable the seccomp sandbox (Linux only)
 const char kEnableSeccompSandbox[]          = "enable-seccomp-sandbox";
 
+// Enable spatial navigation
+const char kEnableSpatialNavigation[]       = "enable-spatial-navigation";
+
 // On platforms that support it, enables smooth scroll animation.
 const char kEnableSmoothScrolling[]         = "enable-smooth-scrolling";
 
 // Enables StatsTable, logging statistics to a global named shared memory table.
 const char kEnableStatsTable[]              = "enable-stats-table";
 
 // Experimentally ensures that each renderer process:
 // 1) Only handles rendering for pages from a single site, apart from iframes.
 // (Note that a page can reference content from multiple origins due to images,
 // JavaScript files, etc.  Cross-site iframes are also loaded in-process.)
@@ skipping 388 matching lines @@
 const char kEnableDeferredImageDecoding[] = "enable-deferred-image-decoding";
 
 // Use a vsync signal from the browser to the renderer to schedule rendering.
 const char kEnableVsyncNotification[] = "enable-vsync-notification";
 
 // Enables history navigation in response to horizontal overscroll.
 const char kEnableOverscrollHistoryNavigation[] =
     "enable-overscroll-history-navigation";
 
 }  // namespace switches