Mojo C++ bindings: make the generator use STL/WTF string/vector/map by default.

ui/events/mojo/BUILD.gn

Index: ui/events/mojo/BUILD.gn
diff --git a/ui/events/mojo/BUILD.gn b/ui/events/mojo/BUILD.gn
index 7179c8f18d8f80846dc3bf17a0e0ca5767bc653c..daa7bb9a70231c31d0144124d4edcb14fa9bc11a 100644
--- a/ui/events/mojo/BUILD.gn
+++ b/ui/events/mojo/BUILD.gn
@@ -16,6 +16,8 @@ mojom("interfaces") {
     "//mojo/common:common_custom_types",
     "//ui/gfx/geometry/mojo",
   ]
+
+  use_new_wrapper_types = false
 }
 
 mojom("test_interfaces") {
@@ -27,4 +29,6 @@ mojom("test_interfaces") {
   public_deps = [
     ":interfaces",
   ]
+
+  use_new_wrapper_types = false
 }