Fix extension bindings injection for iframes (reland)

extensions/renderer/script_context.h

Index: extensions/renderer/script_context.h
diff --git a/extensions/renderer/script_context.h b/extensions/renderer/script_context.h
index bbfd2f6b90edb872edabb62abdf811c8597a2d5b..dd97ac90dc3871d8b7c8d095aec42e33eec09c66 100644
--- a/extensions/renderer/script_context.h
+++ b/extensions/renderer/script_context.h
@@ -5,6 +5,7 @@
 #ifndef EXTENSIONS_RENDERER_SCRIPT_CONTEXT_H_
 #define EXTENSIONS_RENDERER_SCRIPT_CONTEXT_H_
 
+#include <memory>
 #include <string>
 #include <utility>
 #include <vector>
@@ -157,6 +158,13 @@ class ScriptContext : public RequestSender::Source {
   // The returned URL may be invalid.
   static GURL GetDataSourceURLForFrame(const blink::WebFrame* frame);
 
+  // Similar to GetDataSourceURLForFrame, but only returns the data source URL
+  // if the frame's document url is empty and the frame has a security origin
+  // that allows access to the data source url.
+  // TODO(asargent/devlin) - there may be places that should switch to using
+  // this instead of GetDataSourceURLForFrame.
+  static GURL GetAccessCheckedFrameURL(const blink::WebFrame* frame);
+
   // Returns the first non-about:-URL in the document hierarchy above and
   // including |frame|. The document hierarchy is only traversed if
   // |document_url| is an about:-URL and if |match_about_blank| is true.