Deprecate openDatabase and openDatabaseSync in workers.

Source/core/frame/UseCounter.cpp

Index: Source/core/frame/UseCounter.cpp
diff --git a/Source/core/frame/UseCounter.cpp b/Source/core/frame/UseCounter.cpp
index 52b279145ffb7e3b971b04662c40ea34e95614b1..4a55d519c4d1b462f8a5ef9e3083e78204740d06 100644
--- a/Source/core/frame/UseCounter.cpp
+++ b/Source/core/frame/UseCounter.cpp
@@ -733,6 +733,12 @@ String UseCounter::deprecationMessage(Feature feature)
     case SyncXHRWithCredentials:
         return "Setting 'XMLHttpRequest.withCredentials' for synchronous requests is deprecated.";
 
+    case OpenWebDatabaseInWorker:
+        return "'openDatabase' in Workers is deprecated. Please switch to Indexed Database API.";
+
+    case OpenWebDatabaseSyncInWorker:
+        return "'openDatabaseSync' is deprecated. Please switch to Indexed Database API.";
+
     // Features that aren't deprecated don't have a deprecation message.
     default:
         return String();