DataTransfer: Make |types| be a FrozenArray<DOMString>.

third_party/WebKit/Source/core/clipboard/DataObjectTest.cpp

Index: third_party/WebKit/Source/core/clipboard/DataObjectTest.cpp
diff --git a/third_party/WebKit/Source/core/clipboard/DataObjectTest.cpp b/third_party/WebKit/Source/core/clipboard/DataObjectTest.cpp
index 0c28952d5a8aaf7e4e626b8541ebfcc3837fb1a8..fc6f48dc12c03adb235e06c8049a59404eb9764c 100644
--- a/third_party/WebKit/Source/core/clipboard/DataObjectTest.cpp
+++ b/third_party/WebKit/Source/core/clipboard/DataObjectTest.cpp
@@ -18,6 +18,70 @@ class DataObjectTest : public ::testing::Test {
   Persistent<DataObject> data_object_;
 };
 
+class DataObjectObserver : public GarbageCollected<DataObjectObserver>,
+                           public DataObject::Observer {
+  USING_GARBAGE_COLLECTED_MIXIN(DataObjectObserver);
+
+ public:
+  DataObjectObserver() : call_count_(0) {}
+  void OnItemListChanged() override { call_count_++; }
+  size_t call_count() { return call_count_; }
+
+ private:
+  size_t call_count_;
+};
+
+TEST_F(DataObjectTest, DataObjectObserver) {
+  DataObjectObserver* observer = new DataObjectObserver;
+  data_object_->AddObserver(observer);
+
+  data_object_->ClearAll();
+  EXPECT_EQ(0U, data_object_->length());
+  EXPECT_EQ(0U, observer->call_count());
+
+  data_object_->SetData("text/plain", "foobar");
+  EXPECT_EQ(1U, data_object_->length());
+  EXPECT_EQ(1U, observer->call_count());
+
+  DataObjectItem* item = data_object_->Add("bar quux", "text/plain");
+  EXPECT_EQ(nullptr, item);
+  EXPECT_EQ(1U, data_object_->length());
+  EXPECT_EQ(1U, observer->call_count());
+
+  item = data_object_->Add("bar quux", "application/octet-stream");
+  EXPECT_NE(nullptr, item);
+  EXPECT_EQ(2U, data_object_->length());
+  EXPECT_EQ(2U, observer->call_count());
+
+  data_object_->DeleteItem(42);
+  EXPECT_EQ(2U, data_object_->length());
+  EXPECT_EQ(2U, observer->call_count());
+
+  data_object_->DeleteItem(0);
+  EXPECT_EQ(1U, data_object_->length());
+  EXPECT_EQ(3U, observer->call_count());
+
+  DataObjectObserver* observer2 = new DataObjectObserver;
+  data_object_->AddObserver(observer2);
+
+  String file_path = testing::BlinkRootDir();
+  file_path.append("/Source/core/clipboard/DataObjectTest.cpp");
+  data_object_->AddFilename(file_path, String(), String());
+  EXPECT_EQ(2U, data_object_->length());
+  EXPECT_EQ(4U, observer->call_count());
+  EXPECT_EQ(1U, observer2->call_count());
+
+  data_object_->ClearData("application/octet-stream");
+  EXPECT_EQ(1U, data_object_->length());
+  EXPECT_EQ(5U, observer->call_count());
+  EXPECT_EQ(2U, observer2->call_count());
+
+  data_object_->ClearAll();
+  EXPECT_EQ(0U, data_object_->length());
+  EXPECT_EQ(6U, observer->call_count());
+  EXPECT_EQ(3U, observer2->call_count());
+}
+
 TEST_F(DataObjectTest, addItemWithFilenameAndNoTitle) {
   String file_path = testing::BlinkRootDir();
   file_path.append("/Source/core/clipboard/DataObjectTest.cpp");