[heap] Reenable UnmapOnTeardown test

Test now passes even if RO_SPACE sharing is enabled.

Bug: v8:10454
Change-Id: Ic7377c3367199383bb6a96a9beedcc52bbc3362f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2335184
Commit-Queue: Dan Elphick <delphick@chromium.org>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Auto-Submit: Dan Elphick <delphick@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69221}

test/unittests/heap/unmapper-unittest.cc

@@ -272,9 +272,6 @@ TrackingPageAllocator* SequentialUnmapperTest::tracking_page_allocator_ =
 v8::PageAllocator* SequentialUnmapperTest::old_page_allocator_ = nullptr;
 bool SequentialUnmapperTest::old_flag_;
 
-// TODO(v8:7464): Enable these once there is a good way to free the shared
-// read-only space.
-#ifndef V8_SHARED_RO_HEAP
 // See v8:5945.
 TEST_F(SequentialUnmapperTest, UnmapOnTeardownAfterAlreadyFreeingPooled) {
   Page* page = allocator()->AllocatePage(
@@ -334,7 +331,6 @@ TEST_F(SequentialUnmapperTest, UnmapOnTeardown) {
     tracking_page_allocator()->CheckIsFree(page->address(), page_size);
   }
 }
-#endif  // V8_SHARED_RO_HEAP
 
 }  // namespace internal
 }  // namespace v8