MD Settings: Redirect chrome://help and chrome://chrome to About page.

chrome/browser/chrome_content_browser_client.cc

Index: chrome/browser/chrome_content_browser_client.cc
diff --git a/chrome/browser/chrome_content_browser_client.cc b/chrome/browser/chrome_content_browser_client.cc
index b8ee4de63eb65f7835a38e32825d65732622c8cb..5660e22e33c06e1a74443f9dd1cb6165df0ea80d 100644
--- a/chrome/browser/chrome_content_browser_client.cc
+++ b/chrome/browser/chrome_content_browser_client.cc
@@ -532,6 +532,17 @@ bool HandleNewTabPageLocationOverride(
 
 // Handles rewriting Web UI URLs.
 bool HandleWebUI(GURL* url, content::BrowserContext* browser_context) {
+  if (base::FeatureList::IsEnabled(features::kMaterialDesignSettings)) {
+    // Rewrite chrome://help and chrome://chrome to chrome://settings/help.
+    if (url->host() == chrome::kChromeUIHelpHost ||
+        (url->host() == chrome::kChromeUIUberHost &&
+         (url->path().empty() || url->path() == "/"))) {
+      *url = ReplaceURLHostAndPath(*url, chrome::kChromeUISettingsHost,
+                                   chrome::kChromeUIHelpHost);
+      return true;  // Return true to update the displayed URL.
+    }
+  }
+
   // Do not handle special URLs such as "about:foo"
   if (!url->host().empty()) {
     const GURL chrome_url = AddUberHost(*url);
@@ -567,6 +578,13 @@ bool HandleWebUI(GURL* url, content::BrowserContext* browser_context) {
 // Reverse URL handler for Web UI. Maps "chrome://chrome/foo/" to
 // "chrome://foo/".
 bool HandleWebUIReverse(GURL* url, content::BrowserContext* browser_context) {
+  // No need to actually reverse-rewrite the URL, but return true to update the
+  // displayed URL when rewriting chrome://help to chrome://settings/help.
+  if (base::FeatureList::IsEnabled(features::kMaterialDesignSettings) &&
+      url->host() == chrome::kChromeUISettingsHost) {
+    return true;
+  }
+
   if (!url->is_valid() || !url->SchemeIs(content::kChromeUIScheme))
     return false;