Add MD Feedback switch.

chrome/common/chrome_switches.cc

Index: chrome/common/chrome_switches.cc
diff --git a/chrome/common/chrome_switches.cc b/chrome/common/chrome_switches.cc
index b1b16bae6dcf200d499edd9de708e288ae116254..a285110d6de43b7cd82a83cc6c88e551ec36c294 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -424,6 +424,9 @@ const char kEnableGoogleBrandedContextMenu[] =
 // Enables the Material Design version of chrome://extensions.
 const char kEnableMaterialDesignExtensions[] = "enable-md-extensions";
 
+// Enables the Material Design feedback form.
+const char kEnableMaterialDesignFeedback[] = "enable-md-feedback";
+
 // Enables the Material Design policy page at chrome://md-policy.
 const char kEnableMaterialDesignPolicyPage[]  = "enable-md-policy-page";
 
@@ -1309,6 +1312,11 @@ bool MdExtensionsEnabled() {
       ::switches::kEnableMaterialDesignExtensions);
 }
 
+bool MdFeedbackEnabled() {
+  return base::CommandLine::ForCurrentProcess()->HasSwitch(
+      ::switches::kEnableMaterialDesignFeedback);
+}
+
 bool MdPolicyPageEnabled() {
   return base::CommandLine::ForCurrentProcess()->HasSwitch(
       ::switches::kEnableMaterialDesignPolicyPage);