[part 1] Make classes and structures in modules/ fast-allocated.

Source/modules/accessibility/testing/InternalsAccessibility.h

Index: Source/modules/accessibility/testing/InternalsAccessibility.h
diff --git a/Source/modules/accessibility/testing/InternalsAccessibility.h b/Source/modules/accessibility/testing/InternalsAccessibility.h
index 1dec1e845a70e4004ad152cf78dfc8ad2180e0f4..5deaee199ff319ecfa2791e74fbff932c44264ad 100644
--- a/Source/modules/accessibility/testing/InternalsAccessibility.h
+++ b/Source/modules/accessibility/testing/InternalsAccessibility.h
@@ -5,11 +5,14 @@
 #ifndef InternalsAccessibility_h
 #define InternalsAccessibility_h
 
+#include "wtf/Allocator.h"
+
 namespace blink {
 
 class Internals;
 
 class InternalsAccessibility {
+    STATIC_ONLY(InternalsAccessibility);
 public:
     static unsigned numberOfLiveAXObjects(Internals&);
 };