Add more informative messages for DOM exceptions.

Source/modules/webaudio/WaveShaperNode.cpp

 /*
  * Copyright (C) 2011, 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 10 matching lines @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
 
 #if ENABLE(WEB_AUDIO)
 
 #include "modules/webaudio/WaveShaperNode.h"
 
+#include "bindings/v8/ExceptionMessages.h"
 #include "bindings/v8/ExceptionState.h"
 #include "core/dom/ExceptionCode.h"
 #include "wtf/MainThread.h"
 
 namespace WebCore {
 
 WaveShaperNode::WaveShaperNode(AudioContext* context)
     : AudioBasicProcessorNode(context, context->sampleRate())
 {
     ScriptWrappable::init(this);
@@ skipping 16 matching lines @@
 
 void WaveShaperNode::setOversample(const String& type, ExceptionState& es)
 {
     ASSERT(isMainThread());
 
     // This is to synchronize with the changes made in
     // AudioBasicProcessorNode::checkNumberOfChannelsForInput() where we can
     // initialize() and uninitialize().
     AudioContext::AutoLocker contextLocker(context());
 
-    if (type == "none")
+    if (type == "none") {
         waveShaperProcessor()->setOversample(WaveShaperProcessor::OverSampleNone);
-    else if (type == "2x")
+    } else if (type == "2x") {
         waveShaperProcessor()->setOversample(WaveShaperProcessor::OverSample2x);
-    else if (type == "4x")
+    } else if (type == "4x") {
         waveShaperProcessor()->setOversample(WaveShaperProcessor::OverSample4x);
-    else
-        es.throwUninformativeAndGenericDOMException(InvalidStateError);
+    } else {
+        es.throwDOMException(
+            InvalidStateError,
+            ExceptionMessages::failedToSet(
+                "oversample",
+                "WaveShaperNode",
+                "invalid oversample '" + type + "': must be 'none', '2x', or '4x'."));
+    }
 }
 
 String WaveShaperNode::oversample() const
 {
     switch (const_cast<WaveShaperNode*>(this)->waveShaperProcessor()->oversample()) {
     case WaveShaperProcessor::OverSampleNone:
         return "none";
     case WaveShaperProcessor::OverSample2x:
         return "2x";
     case WaveShaperProcessor::OverSample4x:
         return "4x";
     default:
         ASSERT_NOT_REACHED();
         return "none";
     }
 }
 
 } // namespace WebCore
 
 #endif // ENABLE(WEB_AUDIO)