Improve modules' TypeError exception messages.

Source/modules/indexeddb/IDBFactory.cpp

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 79 matching lines @@
     }
 
     blink::Platform::current()->idbFactory()->getDatabaseNames(WebIDBCallbacksImpl::create(request).leakPtr(), createDatabaseIdentifierFromSecurityOrigin(context->securityOrigin()));
     return request;
 }
 
 PassRefPtr<IDBOpenDBRequest> IDBFactory::open(ExecutionContext* context, const String& name, unsigned long long version, ExceptionState& exceptionState)
 {
     IDB_TRACE("IDBFactory::open");
     if (!version) {
-        exceptionState.throwUninformativeAndGenericTypeError();
+        exceptionState.throwTypeError("The version provided must not be 0.");
         return 0;
     }
     return openInternal(context, name, version, exceptionState);
 }
 
 PassRefPtr<IDBOpenDBRequest> IDBFactory::openInternal(ExecutionContext* context, const String& name, int64_t version, ExceptionState& exceptionState)
 {
     blink::Platform::current()->histogramEnumeration("WebCore.IndexedDB.FrontEndAPICalls", IDBOpenCall, IDBMethodsMax);
     ASSERT(version >= 1 || version == IDBDatabaseMetadata::NoIntVersion);
     if (name.isNull()) {
-        exceptionState.throwUninformativeAndGenericTypeError();
+        exceptionState.throwTypeError("The name provided must not be empty.");
         return 0;
     }
     if (!isContextValid(context))
         return 0;
     if (!context->securityOrigin()->canAccessDatabase()) {
         exceptionState.throwSecurityError("access to the Indexed Database API is denied in this context.");
         return 0;
     }
 
     RefPtr<IDBDatabaseCallbacks> databaseCallbacks = IDBDatabaseCallbacks::create();
@@ skipping 13 matching lines @@
 {
     IDB_TRACE("IDBFactory::open");
     return openInternal(context, name, IDBDatabaseMetadata::NoIntVersion, exceptionState);
 }
 
 PassRefPtr<IDBOpenDBRequest> IDBFactory::deleteDatabase(ExecutionContext* context, const String& name, ExceptionState& exceptionState)
 {
     IDB_TRACE("IDBFactory::deleteDatabase");
     blink::Platform::current()->histogramEnumeration("WebCore.IndexedDB.FrontEndAPICalls", IDBDeleteDatabaseCall, IDBMethodsMax);
     if (name.isNull()) {
-        exceptionState.throwUninformativeAndGenericTypeError();
+        exceptionState.throwTypeError("The name provided must not be empty.");
         return 0;
     }
     if (!isContextValid(context))
         return 0;
     if (!context->securityOrigin()->canAccessDatabase()) {
         exceptionState.throwSecurityError("access to the Indexed Database API is denied in this context.");
         return 0;
     }
 
     RefPtr<IDBOpenDBRequest> request = IDBOpenDBRequest::create(context, 0, 0, IDBDatabaseMetadata::DefaultIntVersion);
@@ skipping 18 matching lines @@
 
     if (!first->isValid() || !second->isValid()) {
         exceptionState.throwDOMException(DataError, IDBDatabase::notValidKeyErrorMessage);
         return 0;
     }
 
     return static_cast<short>(first->compare(second.get()));
 }
 
 } // namespace WebCore