[debug] Check if a breakpoint was already inserted

This check skips inserting a breakpoint into the BreakPointInfo if
it has already been inserted before.

Change-Id: Ic773fe1d6b2351bf6069fa0ff002737bd0b03293
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2253851Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Kim-Anh Tran <kimanh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68447}

src/objects/debug-objects.cc

@@ -274,10 +274,13 @@ void BreakPointInfo::SetBreakPoint(Isolate* isolate,
     break_point_info->set_break_points(*break_point);
     return;
   }
-  // If the break point object is the same as before just ignore.
-  if (break_point_info->break_points() == *break_point) return;
   // If there was one break point object before replace with array.
   if (!break_point_info->break_points().IsFixedArray()) {
+    if (IsEqual(BreakPoint::cast(break_point_info->break_points()),
+        *break_point)) {
+          return;
+    }
+
     Handle<FixedArray> array = isolate->factory()->NewFixedArray(2);
     array->set(0, break_point_info->break_points());
     array->set(1, *break_point);