Reland of [heap] Fix CompactionSpace test and move to unittests

test/unittests/heap/spaces-unittest.cc

+// Copyright 2017 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "src/heap/heap-inl.h"
+#include "src/heap/spaces-inl.h"
+#include "src/isolate.h"
+#include "test/unittests/test-utils.h"
+
+namespace v8 {
+namespace internal {
+
+typedef TestWithIsolate SpacesTest;
+
+TEST_F(SpacesTest, CompactionSpaceMerge) {
+  Heap* heap = i_isolate()->heap();
+  OldSpace* old_space = heap->old_space();
+  EXPECT_TRUE(old_space != NULL);
+
+  CompactionSpace* compaction_space =
+      new CompactionSpace(heap, OLD_SPACE, NOT_EXECUTABLE);
+  EXPECT_TRUE(compaction_space != NULL);
+  EXPECT_TRUE(compaction_space->SetUp());
+
+  // Cannot loop until "Available()" since we initially have 0 bytes available
+  // and would thus neither grow, nor be able to allocate an object.
+  const int kNumObjects = 10;
+  const int kNumObjectsPerPage =
+      compaction_space->AreaSize() / kMaxRegularHeapObjectSize;
+  const int kExpectedPages =
+      (kNumObjects + kNumObjectsPerPage - 1) / kNumObjectsPerPage;
+  for (int i = 0; i < kNumObjects; i++) {
+    HeapObject* object =
+        compaction_space->AllocateRawUnaligned(kMaxRegularHeapObjectSize)
+            .ToObjectChecked();
+    heap->CreateFillerObjectAt(object->address(), kMaxRegularHeapObjectSize,
+                               ClearRecordedSlots::kNo);
+  }
+  int pages_in_old_space = old_space->CountTotalPages();
+  int pages_in_compaction_space = compaction_space->CountTotalPages();
+  EXPECT_EQ(kExpectedPages, pages_in_compaction_space);
+  old_space->MergeCompactionSpace(compaction_space);
+  EXPECT_EQ(pages_in_old_space + pages_in_compaction_space,
+            old_space->CountTotalPages());
+
+  delete compaction_space;
+}
+
+}  // namespace internal
+}  // namespace v8