Add --enable-nacl to the whitelisted browser flags that are passed to renderer processes

TEST=manual
BUG= http://code.google.com/p/nativeclient/issues/detail?id=1322 
Review URL: http://codereview.chromium.org/6262009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@72234 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/renderer_host/browser_render_process_host.cc

@@ -679,6 +679,7 @@ void BrowserRenderProcessHost::PropagateBrowserCommandLineToRenderer(
     switches::kDisableAudio,
     switches::kSimpleDataSource,
     switches::kEnableBenchmarking,
+    switches::kEnableNaCl,
     switches::kInternalNaCl,
     switches::kInternalPepper,
     switches::kRegisterPepperPlugins,