Remove incorrect DCHECK at the top of FrameLoader::DidFinishNavigation

Bug: 1106608
Change-Id: Ie71fcdea1186761fd6cc7f32ebf38ee0e497d843
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2316695
Commit-Queue: Dmitry Gozman <dgozman@chromium.org>
Auto-Submit: Nate Chapin <japhet@chromium.org>
Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#791484}

third_party/blink/renderer/core/loader/frame_loader.cc

@@ -400,11 +400,8 @@ void FrameLoader::FinishedParsing() {
 // does not do anything when navigation is in progress, or when loading
 // has finished already. We should call it at the right times.
 void FrameLoader::DidFinishNavigation(NavigationFinishState state) {
-  // We should have either finished the provisional or committed navigation if
-  // this is called. Only delcare the whole frame finished if neither is in
-  // progress.
-  DCHECK((document_loader_ && document_loader_->SentDidFinishLoad()) ||
-         !HasProvisionalNavigation());
+  // Only declare the whole frame finished if the committed navigation is done
+  // and there is no provisional navigation in progress.
   if ((document_loader_ && !document_loader_->SentDidFinishLoad()) ||
       HasProvisionalNavigation()) {
     return;