Web MIDI: add RequestMIDISysExPermission to BrowserContext

chrome/test/base/testing_profile.cc

Index: chrome/test/base/testing_profile.cc
diff --git a/chrome/test/base/testing_profile.cc b/chrome/test/base/testing_profile.cc
index d5218609b49a2e1ff467212bda8b3060d8f48110..45f8dd70df6ebbd92b985d57cbf6483bf549bbb9 100644
--- a/chrome/test/base/testing_profile.cc
+++ b/chrome/test/base/testing_profile.cc
@@ -645,6 +645,15 @@ TestingProfile::GetMediaRequestContextForStoragePartition(
   return NULL;
 }
 
+void TestingProfile::RequestMIDISysExPermission(
+      int render_process_id,
+      int render_view_id,
+      const GURL& requesting_frame,
+      const MIDISysExPermissionCallback& callback) {
+  // Always reject requests for testing.
+  callback.Run(false);
+}
+
 net::URLRequestContextGetter* TestingProfile::GetRequestContextForExtensions() {
   if (!extensions_request_context_.get())
     extensions_request_context_ = new TestExtensionURLRequestContextGetter();