PlzNavigate: inform the WebFrameClient that a form will be submitted

third_party/WebKit/Source/core/loader/FrameLoader.cpp

Index: third_party/WebKit/Source/core/loader/FrameLoader.cpp
diff --git a/third_party/WebKit/Source/core/loader/FrameLoader.cpp b/third_party/WebKit/Source/core/loader/FrameLoader.cpp
index 038cf60a8afc2b21412fab348d49efb7f0661d53..a2e5f377d10796165ae5efb11e578fe29b979f7a 100644
--- a/third_party/WebKit/Source/core/loader/FrameLoader.cpp
+++ b/third_party/WebKit/Source/core/loader/FrameLoader.cpp
@@ -1322,7 +1322,7 @@ bool FrameLoader::shouldClose(bool isReload)
 
 bool FrameLoader::shouldContinueForNavigationPolicy(const ResourceRequest& request, const SubstituteData& substituteData,
     DocumentLoader* loader, ContentSecurityPolicyDisposition shouldCheckMainWorldContentSecurityPolicy,
-    NavigationType type, NavigationPolicy policy, bool replacesCurrentHistoryItem, bool isClientRedirect)
+    NavigationType type, NavigationPolicy policy, bool replacesCurrentHistoryItem, bool isClientRedirect, HTMLFormElement* form)
 {
     // Don't ask if we are loading an empty URL.
     if (request.url().isEmpty() || substituteData.isValid())
@@ -1352,6 +1352,12 @@ bool FrameLoader::shouldContinueForNavigationPolicy(const ResourceRequest& reque
     if (policy == NavigationPolicyHandledByClient) {
         // Mark the frame as loading since the embedder is handling the navigation.
         m_progressTracker->progressStarted();
+
+        // If this is a form submit, dispatch that a form is being submitted
+        // since the embedder is handling the navigation.
+        if (form)
+            client()->dispatchWillSubmitForm(form);

[dcheng, 2016/02/24 21:24:55]

Just curious: shouldn't the embedder "know" it is dealing with a form? It seems
a little unusual that Blink has to tell the embedder about something it should
already know.

[clamy, 2016/02/25 14:34:07]

I'm not sure how exactly the embedder know the navigation is a form: for
example, a form could have been filled, but the user clicked on a link, so we're
not actually submitting the form.

[dcheng, 2016/02/25 21:56:17]

Makes sense, thanks.

+
         return false;
     }
     if (!LocalDOMWindow::allowPopUp(*m_frame) && !UserGestureIndicator::processingUserGesture())
@@ -1372,8 +1378,13 @@ void FrameLoader::startLoad(FrameLoadRequest& frameLoadRequest, FrameLoadType ty
     frameLoadRequest.resourceRequest().setRequestContext(determineRequestContextFromNavigationType(navigationType));
     frameLoadRequest.resourceRequest().setFrameType(m_frame->isMainFrame() ? WebURLRequest::FrameTypeTopLevel : WebURLRequest::FrameTypeNested);
     ResourceRequest& request = frameLoadRequest.resourceRequest();
-    if (!shouldContinueForNavigationPolicy(request, frameLoadRequest.substituteData(), nullptr, frameLoadRequest.shouldCheckMainWorldContentSecurityPolicy(), navigationType, navigationPolicy, type == FrameLoadTypeReplaceCurrentItem, frameLoadRequest.clientRedirect() == ClientRedirect))
+    if (!shouldContinueForNavigationPolicy(request, frameLoadRequest.substituteData(), nullptr,
+        frameLoadRequest.shouldCheckMainWorldContentSecurityPolicy(), navigationType,
+        navigationPolicy, type == FrameLoadTypeReplaceCurrentItem,
+        frameLoadRequest.clientRedirect() == ClientRedirect, frameLoadRequest.form())) {
         return;
+    }
+
     if (!shouldClose(navigationType == NavigationTypeReload))
         return;