[heap] Add V8_NOEXCEPT annotation for GCCallbackTuple

Bug: v8:8616
Change-Id: I0998b437712037277b81eb5d04b734826aabcd46
Reviewed-on: https://chromium-review.googlesource.com/c/1391754
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58529}

src/heap/heap.h

@@ -1350,7 +1350,7 @@ class Heap {
         : callback(callback), gc_type(gc_type), data(data) {}
 
     bool operator==(const GCCallbackTuple& other) const;
-    GCCallbackTuple& operator=(const GCCallbackTuple& other);
+    GCCallbackTuple& operator=(const GCCallbackTuple& other) V8_NOEXCEPT;
 
     v8::Isolate::GCCallbackWithData callback;
     GCType gc_type;