Port messages sent by WebIDBFactoryImpl to Mojo.

third_party/WebKit/Source/modules/indexeddb/WebIDBDatabaseCallbacksImpl.cpp

Index: third_party/WebKit/Source/modules/indexeddb/WebIDBDatabaseCallbacksImpl.cpp
diff --git a/third_party/WebKit/Source/modules/indexeddb/WebIDBDatabaseCallbacksImpl.cpp b/third_party/WebKit/Source/modules/indexeddb/WebIDBDatabaseCallbacksImpl.cpp
index 4b6b8e87603ccf4e2b756924583d64539efe6c18..a79fff198ca1d49a2efc3f94151ac5c1e33d1a61 100644
--- a/third_party/WebKit/Source/modules/indexeddb/WebIDBDatabaseCallbacksImpl.cpp
+++ b/third_party/WebKit/Source/modules/indexeddb/WebIDBDatabaseCallbacksImpl.cpp
@@ -41,25 +41,37 @@ WebIDBDatabaseCallbacksImpl::WebIDBDatabaseCallbacksImpl(
     IDBDatabaseCallbacks* callbacks)
     : m_callbacks(callbacks) {}
 
-WebIDBDatabaseCallbacksImpl::~WebIDBDatabaseCallbacksImpl() {}
+WebIDBDatabaseCallbacksImpl::~WebIDBDatabaseCallbacksImpl() {
+  if (m_callbacks)
+    m_callbacks->webCallbacksDestroyed();
+}
 
 void WebIDBDatabaseCallbacksImpl::onForcedClose() {
-  m_callbacks->onForcedClose();
+  if (m_callbacks)
+    m_callbacks->onForcedClose();
 }
 
 void WebIDBDatabaseCallbacksImpl::onVersionChange(long long oldVersion,
                                                   long long newVersion) {
-  m_callbacks->onVersionChange(oldVersion, newVersion);
+  if (m_callbacks)
+    m_callbacks->onVersionChange(oldVersion, newVersion);
 }
 
 void WebIDBDatabaseCallbacksImpl::onAbort(long long transactionId,
                                           const WebIDBDatabaseError& error) {
-  m_callbacks->onAbort(transactionId,
-                       DOMException::create(error.code(), error.message()));
+  if (m_callbacks) {
+    m_callbacks->onAbort(transactionId,
+                         DOMException::create(error.code(), error.message()));
+  }
 }
 
 void WebIDBDatabaseCallbacksImpl::onComplete(long long transactionId) {
-  m_callbacks->onComplete(transactionId);
+  if (m_callbacks)
+    m_callbacks->onComplete(transactionId);
+}
+
+void WebIDBDatabaseCallbacksImpl::detach() {
+  m_callbacks.clear();
 }
 
 }  // namespace blink