bluetooth: Explain why standard names aren't recognized in error message.

Source/modules/bluetooth/BluetoothUUID.cpp

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "modules/bluetooth/BluetoothUUID.h"
 
 #include "bindings/core/v8/ExceptionState.h"
 #include "bindings/core/v8/ScriptRegexp.h"
 #include "core/dom/ExceptionCode.h"
@@ skipping 293 matching lines @@
     }
 
     if (map->contains(nameStr))
         return BluetoothUUID::canonicalUUID(map->get(nameStr));
 
     StringBuilder errorMessage;
     errorMessage.append("Invalid ");
     errorMessage.append(attributeType);
     errorMessage.append(" name: '");
     errorMessage.append(nameStr);
-    errorMessage.append("'.");
+    errorMessage.append("'. It must be a valid UUID alias (e.g. 0x1234), "
+        "UUID (lowercase hex characters e.g. '00001234-0000-1000-8000-00805f9b34fb'), "
+        "or recognized standard name from ");
+    switch (attribute) {
+    case GATTAttribute::Service:
+        errorMessage.append("https://developer.bluetooth.org/gatt/services/Pages/ServicesHome.aspx"
+            " e.g. 'alert_notification'.");
+        break;
+    case GATTAttribute::Characteristic:
+        errorMessage.append("https://developer.bluetooth.org/gatt/characteristics/Pages/CharacteristicsHome.aspx"
+            " e.g. 'aerobic_heart_rate_lower_limit'.");
+        break;
+    case GATTAttribute::Descriptor:
+        errorMessage.append("https://developer.bluetooth.org/gatt/descriptors/Pages/DescriptorsHomePage.aspx"
+            " e.g. 'gatt.characteristic_presentation_format'.");
+        break;
+    }
     // Otherwise, throw a SyntaxError.
     exceptionState.throwDOMException(SyntaxError, errorMessage.toString());
     return String();
 }
 
 } // namespace
 
 // static
 String BluetoothUUID::getService(StringOrUnsignedLong name, ExceptionState& exceptionState)
 {
@@ skipping 20 matching lines @@
     appendUnsignedAsHexFixedSize(
         alias,
         builder, 8 /* 8 chars or 32 bits, prefix length */,
         Lowercase);
 
     builder.append("-0000-1000-8000-00805f9b34fb");
     return builder.toString();
 }
 
 } // namespace blink