Add use counters for a number of extensions and non-standard APIs

Source/core/html/HTMLPreElement.idl

Index: Source/core/html/HTMLPreElement.idl
diff --git a/Source/core/html/HTMLPreElement.idl b/Source/core/html/HTMLPreElement.idl
index 4c7def615d6167f5767cab3a0d5e9fec620ae568..6224bc901f240448fa4400eae1fb6d7c475d6ee3 100644
--- a/Source/core/html/HTMLPreElement.idl
+++ b/Source/core/html/HTMLPreElement.idl
@@ -22,5 +22,5 @@ interface HTMLPreElement : HTMLElement {
     [Reflect] attribute long width;
 
     // Extensions
-    [Reflect] attribute boolean wrap;
+    [Reflect, MeasureAs=HTMLPreElementWrap] attribute boolean wrap;

[eseidel, 2014/05/02 00:32:10]

We don't have a way in the bindings generator to say that "foo" should just call
"getAttribute("foo")", "setAttribute("foo")"?

[Nils Barth (inactive), 2014/05/02 05:10:58]

It does call getAttribute() - or rather fastGetAttribute() - and setAttribute(),
and in simple cases that's basically all it does.
See v8_attributes.py - specifically getter_base_name() and setter_base_name().

https://code.google.com/p/chromium/codesearch#chromium/src/third_party/WebKit...

Can also see output in V8TestObject.cpp (test cases in TestObject.idl), by
searching for getattribute and setattribute:

https://code.google.com/p/chromium/codesearch#chromium/src/third_party/WebKit...

 };