Add support for command line switches to Features, and as proof that it works,

extensions/common/manifest_constants.cc

Index: extensions/common/manifest_constants.cc
diff --git a/extensions/common/manifest_constants.cc b/extensions/common/manifest_constants.cc
index e8099df4b0813c92070c3332b119369023a67121..2711badad5a239ddc4686cdc433d2452e5e8b17a 100644
--- a/extensions/common/manifest_constants.cc
+++ b/extensions/common/manifest_constants.cc
@@ -271,10 +271,6 @@ const char kChromeVersionTooLow[] =
 const char kDisabledByPolicy[] =
     "This extension has been disabled by your administrator.";
 const char kExpectString[] = "Expect string value.";
-const char kExperimentalFlagRequired[] =
-    "Loading extensions with 'experimental' permission is turned off by "
-    "default. You can enable 'Experimental Extension APIs' "
-    "by visiting chrome://flags.";
 const char kInvalidAboutPage[] = "Invalid value for 'about_page'.";
 const char kInvalidAboutPageExpectRelativePath[] =
     "Invalid value for 'about_page'. Value must be a relative path.";