Make classes and structures in core/html fast-allocated.

Source/core/html/MediaFragmentURIParser.h

Index: Source/core/html/MediaFragmentURIParser.h
diff --git a/Source/core/html/MediaFragmentURIParser.h b/Source/core/html/MediaFragmentURIParser.h
index 31018d3f421bceaa02d7b3592e3773ca4d1a229e..e0a4eda50e382712cdbd123ca607b4fc042d0f64 100644
--- a/Source/core/html/MediaFragmentURIParser.h
+++ b/Source/core/html/MediaFragmentURIParser.h
@@ -27,6 +27,7 @@
 #define MediaFragmentURIParser_h
 
 #include "platform/weborigin/KURL.h"
+#include "wtf/Allocator.h"
 #include "wtf/Vector.h"
 
 namespace blink {
@@ -34,6 +35,7 @@ namespace blink {
 class KURL;
 
 class MediaFragmentURIParser final {
+    STACK_ALLOCATED();
 public:
 
     MediaFragmentURIParser(const KURL&);