Update FileSelectHelper to use RenderFrameHost notifications.

chrome/browser/iframe_browsertest.cc

Index: chrome/browser/iframe_browsertest.cc
diff --git a/chrome/browser/iframe_browsertest.cc b/chrome/browser/iframe_browsertest.cc
index e0853f61b98991ffd32c7f5303cfadb94269debe..fef94500fdff173c7489039629d5c7f660c4fbca 100644
--- a/chrome/browser/iframe_browsertest.cc
+++ b/chrome/browser/iframe_browsertest.cc
@@ -8,10 +8,17 @@
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/test/base/in_process_browser_test.h"
 #include "chrome/test/base/ui_test_utils.h"
+#include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/web_contents.h"
+#include "content/public/test/browser_test_utils.h"
 #include "url/gurl.h"
 
 class IFrameTest : public InProcessBrowserTest {
+ public:
+  void SetUpOnMainThread() override {
+    ASSERT_TRUE(embedded_test_server()->Start());
+  }
+
  protected:
   void NavigateAndVerifyTitle(const char* file, const char* page_title) {
     GURL url = ui_test_utils::GetTestUrl(
@@ -30,3 +37,37 @@ IN_PROC_BROWSER_TEST_F(IFrameTest, Crash) {
 IN_PROC_BROWSER_TEST_F(IFrameTest, InEmptyFrame) {
   NavigateAndVerifyTitle("iframe_in_empty_frame.html", "iframe test");
 }
+
+// Test for https://crbug.com/621076. It ensures that file chooser triggered
+// by an iframe, which is destroyed before the chooser is closed, does not
+// result in a use-after-free condition.
+// Note: This test is disabled temporarily to track down a memory leak reported
+// by the ASan bots. It will be enabled once the root cause is found.
+IN_PROC_BROWSER_TEST_F(IFrameTest, DISABLED_FileChooserInDestroyedSubframe) {
+  content::WebContents* tab =
+      browser()->tab_strip_model()->GetActiveWebContents();
+  GURL file_input_url(embedded_test_server()->GetURL("/file_input.html"));
+
+  // Navigate to a page, which contains an iframe, and navigate the iframe
+  // to a document containing a file input field.
+  // Note: For the bug to occur, the parent and child frame need to be in
+  // the same site, otherwise they would each get a RenderWidgetHost and
+  // existing code will properly clear the internal state.
+  ui_test_utils::NavigateToURL(browser(),
+                               embedded_test_server()->GetURL("/iframe.html"));
+  NavigateIframeToURL(tab, "test", file_input_url);
+
+  // Invoke the file chooser and remove the iframe from the main document.
+  content::RenderFrameHost* frame = ChildFrameAt(tab->GetMainFrame(), 0);
+  EXPECT_TRUE(frame);
+  EXPECT_EQ(frame->GetSiteInstance(), tab->GetMainFrame()->GetSiteInstance());
+  EXPECT_TRUE(
+      ExecuteScript(frame, "document.getElementById('fileinput').click();"));
+  EXPECT_TRUE(ExecuteScript(tab->GetMainFrame(),
+                            "document.body.removeChild("
+                            "document.querySelectorAll('iframe')[0])"));
+  ASSERT_EQ(nullptr, ChildFrameAt(tab->GetMainFrame(), 0));
+
+  // On ASan bots, this test should succeed without reporting use-after-free
+  // condition.
+}