[heap] make inline allocation step size dynamic

test/cctest/test-spaces.cc

Index: test/cctest/test-spaces.cc
diff --git a/test/cctest/test-spaces.cc b/test/cctest/test-spaces.cc
index e11d82b03b965a6d7d06dd7ffa176f50aecae0c5..2be94b3dfe069077b67dd5c5c53e9afbe3db4b84 100644
--- a/test/cctest/test-spaces.cc
+++ b/test/cctest/test-spaces.cc
@@ -888,3 +888,35 @@ UNINITIALIZED_TEST(InlineAllocationObserver) {
   }
   isolate->Dispose();
 }
+
+
+UNINITIALIZED_TEST(InlineAllocationObserverCadence) {
+  v8::Isolate::CreateParams create_params;
+  create_params.array_buffer_allocator = CcTest::array_buffer_allocator();
+  v8::Isolate* isolate = v8::Isolate::New(create_params);
+  {
+    v8::Isolate::Scope isolate_scope(isolate);
+    v8::HandleScope handle_scope(isolate);
+    v8::Context::New(isolate)->Enter();
+
+    Isolate* i_isolate = reinterpret_cast<Isolate*>(isolate);
+
+    NewSpace* new_space = i_isolate->heap()->new_space();
+
+    Observer observer1(512);
+    new_space->AddInlineAllocationObserver(&observer1);
+    Observer observer2(576);
+    new_space->AddInlineAllocationObserver(&observer2);
+
+    for (int i = 0; i < 512; ++i) {
+      AllocateUnaligned(new_space, 32);
+    }
+
+    new_space->RemoveInlineAllocationObserver(&observer1);
+    new_space->RemoveInlineAllocationObserver(&observer2);
+
+    CHECK_EQ(observer1.count(), 30);
+    CHECK_EQ(observer2.count(), 26);
+  }
+  isolate->Dispose();
+}