PlzNavigate: don't stop all loaders when renderer-initiated nav fails

third_party/WebKit/Source/web/WebLocalFrameImpl.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 2146 matching lines @@
   if (!sourceLocation.url.isNull()) {
     source =
         SourceLocation::create(sourceLocation.url, sourceLocation.lineNumber,
                                sourceLocation.columnNumber, nullptr);
   }
   MixedContentChecker::mixedContentFound(
       frame(), mainResourceUrl, mixedContentUrl, requestContext, wasAllowed,
       hadRedirect, std::move(source));
 }
 
+void WebLocalFrameImpl::clientDroppedNavigation() {
+  if (frame())

[dcheng, 2017/03/22 19:00:50]

Nit: is it possible to DCHECK() this?

There are only two times this would be null:
- The frame is not completely initialized, but PlzNavigate should not be active
for that frame then.
- The frame is detached, but then IPCs shouldn't be routed to the RenderFrame.

+    frame()->loader().clientDroppedNavigation();
+}
+
 void WebLocalFrameImpl::sendOrientationChangeEvent() {
   if (!frame())
     return;
 
   // Screen Orientation API
   if (ScreenOrientationControllerImpl::from(*frame()))
     ScreenOrientationControllerImpl::from(*frame())->notifyOrientationChanged();
 
   // Legacy window.orientation API
   if (RuntimeEnabledFeatures::orientationEventEnabled() && frame()->domWindow())
@@ skipping 328 matching lines @@
         createMarkup(startPosition, endPosition, AnnotateForInterchange,
                      ConvertBlocksToInlines::NotConvert, ResolveNonLocalURLs);
   } else {
     clipHtml =
         createMarkup(endPosition, startPosition, AnnotateForInterchange,
                      ConvertBlocksToInlines::NotConvert, ResolveNonLocalURLs);
   }
 }
 
 }  // namespace blink