HTMLCanvasElement.toDataURL should use IDL 'any' to avoid using custom binding.

Source/core/html/HTMLCanvasElement.cpp

Index: Source/core/html/HTMLCanvasElement.cpp
diff --git a/Source/core/html/HTMLCanvasElement.cpp b/Source/core/html/HTMLCanvasElement.cpp
index 7cdc91b8fb9600d5f5d035b92dc15a92d23a79c4..b49e13120cb5ecb49f152ca83bed4c5d554e9b9d 100644
--- a/Source/core/html/HTMLCanvasElement.cpp
+++ b/Source/core/html/HTMLCanvasElement.cpp
@@ -485,14 +485,22 @@ String HTMLCanvasElement::toDataURLInternal(const String& mimeType, const double
     return buffer()->toDataURL(encodingMimeType, quality);
 }
 
-String HTMLCanvasElement::toDataURL(const String& mimeType, const double* quality, ExceptionState& exceptionState) const
+String HTMLCanvasElement::toDataURL(const String& mimeType, const ScriptValue& qualityArgument, ExceptionState& exceptionState) const
 {
     if (!originClean()) {
         exceptionState.throwSecurityError("Tainted canvases may not be exported.");
         return String();
     }
-
-    return toDataURLInternal(mimeType, quality, BackBuffer);
+    double quality;
+    double* qualityPtr = nullptr;
+    if (!qualityArgument.isEmpty()) {
+        v8::Local<v8::Value> v8Value = qualityArgument.v8Value();
+        if (v8Value->IsNumber()) {
+            quality = v8Value->NumberValue();
+            qualityPtr = &quality;
+        }
+    }
+    return toDataURLInternal(mimeType, qualityPtr, BackBuffer);
 }
 
 SecurityOrigin* HTMLCanvasElement::securityOrigin() const