Revert r414590

third_party/WebKit/Source/core/html/HTMLFormElement.cpp

Index: third_party/WebKit/Source/core/html/HTMLFormElement.cpp
diff --git a/third_party/WebKit/Source/core/html/HTMLFormElement.cpp b/third_party/WebKit/Source/core/html/HTMLFormElement.cpp
index 3e145614b542b71d9beab41bc90788b2d360dd38..dd75c5daae1fbcb830b111b104382efebc578db8 100644
--- a/third_party/WebKit/Source/core/html/HTMLFormElement.cpp
+++ b/third_party/WebKit/Source/core/html/HTMLFormElement.cpp
@@ -347,12 +347,9 @@ void HTMLFormElement::submit(Event* event,
   if (!view || !frame || !frame->page())
     return;
 
-  // https://html.spec.whatwg.org/multipage/forms.html#form-submission-algorithm
-  // 2. If form document is not connected, has no associated browsing context,
-  // or its active sandboxing flag set has its sandboxed forms browsing
-  // context flag set, then abort these steps without doing anything.
+  // See crbug.com/586749.
   if (!isConnected())
-    return;
+    UseCounter::count(document(), UseCounter::FormSubmissionNotInDocumentTree);
 
   if (m_isSubmitting)
     return;