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 11d7af666f16bec556db17ca607e58a4a9e83345..62a33b31167fc3e3bb5a99d68f6b57507c920734 100644
--- a/Source/core/testing/Internals.cpp
+++ b/Source/core/testing/Internals.cpp
@@ -1010,6 +1010,9 @@ 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;
 }
 
@@ -1030,6 +1033,9 @@ 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);
 }
 
 void Internals::setEditingValue(Element* element, const String& value, ExceptionState& exceptionState)