Add Autofill preview support for <select> input fields

Source/core/testing/Internals.cpp

Index: Source/core/testing/Internals.cpp
diff --git a/Source/core/testing/Internals.cpp b/Source/core/testing/Internals.cpp
index 09f35e51cbcb35b1e3568753d9fae31b5a0fa531..76429de2663e83f8d96240c8d67dad7a3703de2c 100644
--- a/Source/core/testing/Internals.cpp
+++ b/Source/core/testing/Internals.cpp
@@ -1046,6 +1046,9 @@ String Internals::suggestedValue(Element* element, ExceptionState& exceptionStat
 
     if (element->hasTagName(textareaTag))
         suggestedValue = toHTMLTextAreaElement(element)->suggestedValue();
+
+    if (element->hasTagName(selectTag))
+        suggestedValue = toHTMLSelectElement(element)->suggestedValue();
     return suggestedValue;
 }
 
@@ -1066,6 +1069,43 @@ void Internals::setSuggestedValue(Element* element, const String& value, Excepti
 
     if (element->hasTagName(textareaTag))
         toHTMLTextAreaElement(element)->setSuggestedValue(value);
+
+    if (element->hasTagName(selectTag))
+        toHTMLSelectElement(element)->setSuggestedValue(value);
+}
+
+String Internals::originalValue(Element* element, ExceptionState& exceptionState)
+{
+    if (!element) {
+        exceptionState.throwUninformativeAndGenericDOMException(InvalidAccessError);
+        return String();
+    }
+
+    if (!element->isFormControlElement()) {
+        exceptionState.throwUninformativeAndGenericDOMException(InvalidNodeTypeError);
+        return String();
+    }
+
+    String originalValue;
+    if (element->hasTagName(selectTag))
+        originalValue = toHTMLSelectElement(element)->originalValue();
+    return originalValue;
+}
+
+void Internals::setOriginalValue(Element* element, const String& value, ExceptionState& exceptionState)
+{
+    if (!element) {
+        exceptionState.throwUninformativeAndGenericDOMException(InvalidAccessError);
+        return;
+    }
+
+    if (!element->isFormControlElement()) {
+        exceptionState.throwUninformativeAndGenericDOMException(InvalidNodeTypeError);
+        return;
+    }
+
+    if (element->hasTagName(selectTag))
+        toHTMLSelectElement(element)->setOriginalValue(value);
 }
 
 void Internals::setEditingValue(Element* element, const String& value, ExceptionState& exceptionState)