Enable delegate to override SaveToFile and AppendToFile.

brightray/browser/inspectable_web_contents_delegate.h

@@ -20,6 +20,12 @@ class InspectableWebContentsDelegate {
   // the default behavior.
   // Receiver is given the chance to change the |dock_side|.
   virtual bool DevToolsShow(std::string* dock_side) { return false; }
+
+  // Requested by WebContents of devtools.
+  virtual void DevToolsSaveToFile(
+      const std::string& url, const std::string& content, bool save_as) {}
+  virtual void DevToolsAppendToFile(
+      const std::string& url, const std::string& content) {}
 };
 
 }  // namespace brightray

brightray/browser/inspectable_web_contents_impl.cc

@@ -153,10 +153,14 @@ void InspectableWebContentsImpl::OpenInNewTab(const std::string& url) {
 
 void InspectableWebContentsImpl::SaveToFile(
     const std::string& url, const std::string& content, bool save_as) {
+  if (delegate_)
+    delegate_->DevToolsSaveToFile(url, content, save_as);
 }
 
 void InspectableWebContentsImpl::AppendToFile(
     const std::string& url, const std::string& content) {
+  if (delegate_)
+    delegate_->DevToolsAppendToFile(url, content);
 }
 
 void InspectableWebContentsImpl::RequestFileSystems() {