Add webusb notification UI code

chrome/browser/browser_process_impl.h

Index: chrome/browser/browser_process_impl.h
diff --git a/chrome/browser/browser_process_impl.h b/chrome/browser/browser_process_impl.h
index 5f2628e2d0d213a6f5c5bef6772bea65b21da89b..887b4aa12d0ee3ba69d4c0b4452652835332c3b7 100644
--- a/chrome/browser/browser_process_impl.h
+++ b/chrome/browser/browser_process_impl.h
@@ -51,6 +51,10 @@ class BrowserPolicyConnector;
 class PolicyService;
 };
 
+namespace webusb {
+class WebUsbBrowserClient;
+};
+
 // Real implementation of BrowserProcess that creates and returns the services.
 class BrowserProcessImpl : public BrowserProcess,
                            public base::NonThreadSafe {
@@ -321,6 +325,10 @@ class BrowserProcessImpl : public BrowserProcess,
 
   ShellIntegration::DefaultWebClientState cached_default_web_client_state_;
 
+#if !defined(OS_ANDROID) && !defined(OS_IOS)
+  scoped_ptr<webusb::WebUsbBrowserClient> webusb_browser_client_;
+#endif
+
   DISALLOW_COPY_AND_ASSIGN(BrowserProcessImpl);
 };