Make //mojo/edk/js a component.

mojo/edk/js/mojo_runner_delegate.h

Index: mojo/edk/js/mojo_runner_delegate.h
diff --git a/mojo/edk/js/mojo_runner_delegate.h b/mojo/edk/js/mojo_runner_delegate.h
index a76460c56f400c1b13093db8a1f7d8e2016b7dd4..9ab325c8dfb484e4895cddd9f226c2e4db109dc8 100644
--- a/mojo/edk/js/mojo_runner_delegate.h
+++ b/mojo/edk/js/mojo_runner_delegate.h
@@ -7,13 +7,14 @@
 
 #include "base/macros.h"
 #include "gin/modules/module_runner_delegate.h"
+#include "mojo/edk/js/js_export.h"
 #include "mojo/public/c/system/core.h"
 
 namespace mojo {
 namespace edk {
 namespace js {
 
-class MojoRunnerDelegate : public gin::ModuleRunnerDelegate {
+class MOJO_JS_EXPORT MojoRunnerDelegate : public gin::ModuleRunnerDelegate {
  public:
   MojoRunnerDelegate();
   ~MojoRunnerDelegate() override;