Track child web contents

atom/browser/child_web_contents_tracker.cc

@@ -0,0 +1,28 @@
+#include "child_web_contents_tracker.h"
+#include <unordered_set>
+
+namespace atom {
+
+namespace {
+
+std::unordered_set<content::WebContents*> g_child_web_contents;
+
+}  // namespace
+
+ChildWebContentsTracker::ChildWebContentsTracker(
+    content::WebContents* web_contents)
+    : content::WebContentsObserver(web_contents) {
+  g_child_web_contents.insert(web_contents);
+}
+
+bool ChildWebContentsTracker::IsChildWebContents(
+    content::WebContents* web_contents) {
+  return g_child_web_contents.find(web_contents) != g_child_web_contents.end();
+}
+
+void ChildWebContentsTracker::WebContentsDestroyed() {
+  g_child_web_contents.erase(web_contents());
+  delete this;
+}
+
+}  // namespace atom