Set default document urls to 'about:blank'.

third_party/WebKit/Source/core/dom/Document.h

Index: third_party/WebKit/Source/core/dom/Document.h
diff --git a/third_party/WebKit/Source/core/dom/Document.h b/third_party/WebKit/Source/core/dom/Document.h
index 43bfce85ce45d0317fea19669ca562fbf15bdc1d..d93cbe119cab4b887a4ccc2ae70b9db03484b3c9 100644
--- a/third_party/WebKit/Source/core/dom/Document.h
+++ b/third_party/WebKit/Source/core/dom/Document.h
@@ -1300,6 +1300,14 @@ class CORE_EXPORT Document : public ContainerNode,
   void incrementPasswordCount();
   void decrementPasswordCount();
 
+  // Set the default Document URLs to about:blank.
+  KURL urlForBinding() {

[tkent, 2017/03/20 23:06:54]

Let's declare urlForBinding() around url(), and add comments to both of url()
and urlForBinding() to explain their differences.

Also, move the function definition to Document.cpp.  We want to avoid inline
function definitions if it's not just one expression.

+    if (!url().isNull()) {
+      return url();
+    }
+    return blankURL();
+  }
+
  protected:
   Document(const DocumentInit&, DocumentClassFlags = DefaultDocumentClass);