Convert --enable-md-history to a feature flag.

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 b1be5b9616a1f3d976ac6b18292581f5f5dca6e8..f8efe194c9b148e637a6d1bd5fa288b8e74f1078 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -426,9 +426,6 @@ const char kEnableFastUnload[] = "enable-fast-unload";
 // Enables the Material Design version of chrome://extensions.
 const char kEnableMaterialDesignExtensions[] = "enable-md-extensions";
 
-// Enables the Material Design version of chrome://history.
-const char kEnableMaterialDesignHistory[] = "enable-md-history";
-
 // Enables the Material Design policy page at chrome://md-policy.
 const char kEnableMaterialDesignPolicyPage[]  = "enable-md-policy-page";
 
@@ -695,6 +692,11 @@ const char kLocalNtpReload[]                = "local-ntp-reload";
 // Makes Chrome default browser
 const char kMakeDefaultBrowser[]            = "make-default-browser";
 
+// Enables or disables the Material Design version of chrome:://history.
+const base::Feature kMaterialDesignHistoryFeature {
+  "UsesMaterialDesignHistory", base::FEATURE_DISABLED_BY_DEFAULT
+};
+
 // Forces the maximum disk space to be used by the media cache, in bytes.
 const char kMediaCacheSize[]                = "media-cache-size";
 
@@ -1347,8 +1349,8 @@ bool MdExtensionsEnabled() {
 }
 
 bool MdHistoryEnabled() {
-  return base::CommandLine::ForCurrentProcess()->HasSwitch(
-      ::switches::kEnableMaterialDesignHistory);
+  return base::FeatureList::IsEnabled(
+      ::switches::kMaterialDesignHistoryFeature);
 }
 
 bool MdPolicyPageEnabled() {