Blank UI for web component tests.

chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc

Index: chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc
diff --git a/chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc b/chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc
index fc43f0d61a8ed563fc228dff359009de716304e8..7328bd7c3016b8aef947f05b110895947e7f0546 100644
--- a/chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc
+++ b/chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc
@@ -51,6 +51,7 @@
 #include "chrome/browser/ui/webui/translate_internals/translate_internals_ui.h"
 #include "chrome/browser/ui/webui/user_actions/user_actions_ui.h"
 #include "chrome/browser/ui/webui/version_ui.h"
+#include "chrome/browser/ui/webui/web_component_test_ui.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/common/url_constants.h"
@@ -356,6 +357,8 @@ WebUIFactoryFunction GetWebUIFactoryFunction(WebUI* web_ui,
     return &NewWebUI<UserActionsUI>;
   if (url.host() == chrome::kChromeUIVersionHost)
     return &NewWebUI<VersionUI>;
+  if (url.host() == chrome::kChromeUIWebComponentTestHost)

[James Hawkins, 2015/05/14 15:16:09]

How can we mitigate this being accessible outside of a testing environment?  I'm
concerned about the security implications of this infrastructure.

[michaelpg, 2015/05/14 19:06:31]

We could put it behind a flag, but I don't think that's warranted. This is a
blank Web UI so it can't do anything more than other Web UI can do.

In a follow-up CL we'll add mocha.js to this UI. So separately, we should figure
out a way to only include mocha when needed for testing. That discussion is
here:
https://codereview.chromium.org/1124873002/diff/80001/chrome/browser/browser_...

+    return &NewWebUI<WebComponentTestUI>;
 
   /****************************************************************************
    * OS Specific #defines