[include] Add TryCatch and Extension to v8-forward.h

Bug: v8:11965
Change-Id: Ifa8946b28aad681bf3a13861db8f02d8e1a51730
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3178960
Auto-Submit: Dan Elphick <delphick@chromium.org>
Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77014}

include/v8-forward.h

@@ -27,6 +27,7 @@ class Context;
 class DataView;
 class Data;
 class Date;
+class Extension;
 class External;
 class FixedArray;
 class Float32Array;
@@ -63,6 +64,7 @@ class StringObject;
 class Symbol;
 class SymbolObject;
 class Template;
+class TryCatch;
 class TypedArray;
 class Uint16Array;
 class Uint32;